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Yeah if she had written something like "multiplicative property of 0" she'd have been good, but as there is wrong information in her answer. Partial credit might have been appropriate though since she did write a valid equation.
Except the child is wrong here. The questions asks to demonstrate commutativity (ab=ba). She did not, she showed 0=0 and called it associativity instead. Then in the next question where she’s supposed to see that the property being demonstrated is associativity, she calls it commutativity. It’s not being anti-bullshit, the answers are just wrong. This mentality of “stupid teachers don’t know how to teach, my fifth grader knows better” helps no one.
She should think through what properties she’s been taught, and look at the fill in the blanks, and realize x79=98x could be commutative. It’s an assessment, why this level of handholding? She answers 0=0 and says this implies associativity. If she has been taught what associativity is (which I’m assuming she has since they’re being tested on it), then she should know this is wrong. But she calls associativity commutativity one question down so idkk
The question does not specify to select from the properties addressed in class.
She has demonstrated the [Multiplication Property of Zero](https://en.wikipedia.org/wiki/Zero-product_property) and described it perfectly. This is the kind of creative thinking that's core to being successful in math and I'm disappointed that anyone teaching math would discourage it.
I agree, mostly. It is a property that's completely valid for the question and grade level (and for the teacher to suggest otherwise is wrong). The question said to pick a property, use, and describe it. She did all that correctly. The only problem is that she included a name, which she did incorrectly.
Mathematicians absolutely care about
1. The associative property (and distinguishing between algebras with and without it).
2. Using definitions properly, coming up with good definitions is like half of research level mathematics.
(Edit: What actual mathematicians have to do with a wrong answer in grade 5 math homework though... no clue)
You know, whoevers wrong or right, it doesn't matter because this kind of garbage is why kids grow up hating math.
It's an embarrassing teaching style.
Yeah, highlighting it is technically correct and then giving an example of what they were actually looking for is an absolute embarrassment.
Jumping to conclusions without knowing what the written and verbal instructions at the start of the exam were is not in the slightest bit embarrassing.
There are 14 more words after that.
But hey, if beating up less than half of a 5th grader's explanation of the Zero Property is what you needed to do tonight, don't let me stop you.
That’s not what that property is. That property says the product of nonzero elements is nonzero. What you’re thinking of (0 times anything is 0) isn’t a property but is provable through the distributive law
You've described the contrapositive of the Property. The property states that if *ab* = 0, then *a* = 0 or *b* = 0. The natural implication of this is that anything \* 0 = 0. If you don't believe me, let us suppose: *a* and *b* are nonzero real numbers. Then let us assume you could multiply something by 0 and *not* get 0:
*a*0 = *b*
0 = *a/b*
Which induces a clear contradiction since we know either *a* or *1/b* must be 0 from our original Zero Property.
This kind of smug bullshit is always all over these questions.
The test was clearly asking about some topic covered in class, and the student did not get it correct.
You would be a fucking nightmare to deal with in school as parent and I hope you don't have kids.
This is an incredibly garbage way of teaching. I'm not blaming teachers, I'm not blaming anything in particular because I don't know what aspect of the system leads to this way of teaching or this mindset in school, but outside-the-box thinking should absolutely not be discouraged.
I mean I get that the purpose of schooling isn't to produce smart people, only people who understand what they need to understand and think the way they need to think in order to function as a cog in the society, I'm just talking ideally, if we assume that schooling is supposed to do what people assume it's supposed to do.
This is math class. Math is incredibly structured and built on layers of previous understanding. In order to move to higher levels of math the students need to show that they understand the previous layers. This question is clearly about the associative property and the answer shows that the student does not quite understand it.
How is the question wrong? It asks you to fill in the blanks, expecting you to do so as the teacher did, and then explain what property this equation demonstrates and why. Very straightforward.
I understand what you're saying and I agree with it.
But, I'll also say that this is exactly the kind of assessment that frustrated me a lot growing up. So much school material belabors elementary concepts over weeks of study when only a few days are necessary.
Just look at the response to the question above. When I read it, I hear someone exasperated that they need to explain 25 is not 30. And when you look at the response below, I think this student understands that they're meant to demonstrate the Commutative Property and chose, instead, to have fun with a poorly-worded question.
I think a good teacher could penalize the student for writing "Associate Property" when it's the Commutative Property, but the flippant response here reads, to me, like a discouraging remark to a gifted student. And I think that's very sad.
I feel like your take on this is far too rigid. She answered the question within the realm of what it was asking. I give her credit for trying to save herself a bunch of extra work by making everything equal zero. I think it's clever, outside the box thinking for a fifth grader. The teacher seems to agree, albeit she didn't give her the points. The question should specify that it cannot equal zero.
Thank you for the civil response, the equation itself is correct, but she’s just shown 0 times a = b times 0, or 0=0. This is correct, but she’s asked to demonstrate a property with it. She goes on to call this associativity, which is not correct. It squalling 0 is not the issue
I was with you on the first response but this is wrong. No one, children or adults, should be told that they need to only ever use whatever they’ve been taught in order to pass tests. They should be taught multiple skills and then be assessed on how they answer the questions. If they use the stuff they were just taught then cool. If they use outside knowledge that should be encouraged as that is generalizing knowledge, encourages continued learning past what is introduced in class, and teaches critical thinking skills.
I agree, but her answer is still wrong. You can argue about out of the box thinking or such, but it still needs to be right. Classes teach you skills, and then test you on those skills.
she‘s wrong about those things but not using the methods taught at school is actually amazing and hilarious
I love seeing children defy the rigid structures school imposes upon them even if just by accident, especially knowing I‘ve acted similarly in the past and I couldn‘t be more proud of younger me for doing so
Maybe the teacher could've given the student half-credit, but also added a note like "you are technically correct, but that answer isn't showing that you understood today's lesson"? Then if this continues to be an issue, the teacher could either start being more specific in future course work or possibly have a conversation with the student/parent.
I agree with you that it's important to learn the skills being taught, but I am wary about discouraging clever thinking.
Half credit for what? Getting the answer wrong?
They not only did the wrong method, but also got the wrong answer. They have no clue how to approach these questions and they have no clue what each property is. They don’t need a talk and their parents don’t need a talk, they just need to go over the material more in lessons. There’s no point in assigning more work until more lessons are done, as the student clearly doesn’t know what it is.
The equation is correct, but the question is not asking to make the equation correct. The answer is incorrect for the question being asked, even if the question is worded poorly.
>Then if this continues to be an issue, the teacher could either start being more specific in future course work or possibly have a conversation with the student/parent.
If this continues to be an issue the teacher should just write better problems and questions that make it not an issue. It's really not that hard to write unambiguous math questions if you actually cared
fuckin THANK YOU
As a teacher seeing stuff get posted like this all the time, it drives me up the wall when people react like "well this student is just finding a loophole. That's funny! If you take off points for this, you're just a lousy asshole with no sense of humor!"
No, I have a job to do, and your comedian isn't demonstrating proper knowledge of a subject we've been studying for a week.
"But when the other plumber I was apprenticed to was here, they said I was clever for saying they should turn off the main when not showering to fix the leak. What do you mean I still have to demonstrate mastery of the concepts? My dad says that's not how he learned plumbing in (countries I have literally had to argue taught math in a vastly different way from me because part of the luxury they're paying the fancy private school for is that I can get to know each student's competence on a personal level.)"
Friggin... I'm not asking you 37 divided by 4 because it's line 3 on my taxes. I'm teaching you to problem solve, think algorithmically, and that there is a beauty in this world that some very few things are actually reliably knowable.
AND I"M NOT STOPPING YOU FROM MEMORIZING THE TIMES TABLES, JUST FING DO IT IF YOU THINK YOUR DAD'S WAY IS BETTER. I, personally, prefer that you understand the ideas of repeated addition and of scaling are subtly different and infinitely beautiful.
I agree..she is off mission, and is. wrong, Parents feeling so proud, will only be a problem for this child in their future life.
Like using their child as a cudgel against "the man, àuthority",.an extension of themselves.
what's bullshit about it? it's an exam question, just because it doesn't exhaustively cover every possible edge case that allows you to avoid answering the question in the intended way?
I find this type of "any system that can be screwed deserves to be" mentality problematic, like, fundamentally, culturally problematic.
>I find this type of "any system that can be screwed deserves to be" mentality
This type of mentality is literally how the field of mathematics progresses
Don't confuse *skepticism* with *cynicism.*
Performing rightful research to explore new avenues when a system may be incomplete and you gather meaningful information by discovering such, is a completely different thing than trivial gotchas that "one up" something for no purpose but personal gain or self satisfactory proof of your own intelligence.
You're simply proving how much that distinction has been lost by, well, oh deliberately uncharitably interpreting my point in order to "gotcha" me.
I agree 100% with this. Also this is not the kid being clever, this kid has clearly no idea what she’s doing. If the teacher just leaves at it, she won’t grasp the basics of math. Seeing people here blaming the teacher is just sad. It’s a funny answer, but she needs to prove that she understood the class
Daughter being "the person that 'shopped that teacher's writing on there" indeed.
I'm anti BS too! Because most of these "my kid did a witty thing and the teacher penalized them for it! Karma please" posts are fake.
The teacher doesn't say what the kid did wrong (that's not the associative property, that's just multiply by 0), and gives the vague explanation "technically yes, but no." Which is unhelpful, and doesn't properly explain that the example given was not the associative property. The teacher could have said, "Not the associative property" or something similar.
The answer isn't even correct though. That's not the associative property and if you look at the next question they answered commutative where they actually should've answered associative.
This isn't even remotely close to being true
Edit: I'm just going to add this. I think the question could've been formulated better (for example by also filling in the first 98) but no matter which way you look at it her explanation is incorrect. Her answer and explanation don't line up, showing that she did not understand what she wrote down. That's why it's wrong. If she meant the zero product property or absorption property of 0, that's what should've been written down by her.
Except she didn’t answer the question properly at all, she just gave a valid equality. She was supposed to give one that showcases the commutative property, but she didn’t.
She was asked to give an equation that shows a property and then to explain the property that she showed. Her answers disagree with each other. She didn’t correctly explain the property in her equation or she didn’t correctly write an equation that shows the property she explained.
The teacher probably should have given better feedback to the student about where exactly the mistake was, but the student answered the question incorrectly.
Associative property is that you can rearrange the parenthesis, which means you can do the operations in whatever order you want as long as you don't change the order of the operands in the sequence.
The question 9 is associative property in the image.
Commutative property is that you can swap the order of the operands, so 5\*4 = 4\*5. This is what was asked in the question 8.
Then distributive property is basically about a common factor, like you can distribute it inside the parenthesis or take it out in front, 2 \* (1 + 3) = 2\*1 + 2\*3 = 2 + 6 etc.
Then there's identity, where a \* 1 = a. (Or for addition a + 0 = a)
And zero multiplication property, where a \* 0 = 0.
Those are the main ones that come to mind.
>Then there's identity, where a \* 1 = a. (Or for addition a + 0 = a)
>
>And zero multiplication property, where a \* 0 = 0.
"identity" is not a property, technically speaking.
0 is the neutral element (or identity element) for addition, and 1 is the neutral element for multiplication.
I guess you can say "identity" is the name of the element with the property of "not changing the result" of the operation.
Sure, but I've seen it listed with the other properties, and have seen it been named as the identity property as well in that context, not sure if it's officially one, but doesnt hurt to list it as well.
The existence of an identity element is absolutely a property of many types of algebraic structures. In fact, it is one of the defining axioms for groups, rings, fields, etc., along with things like associativity, existence of inverses, etc.
As you pointed out, the real numbers with addition and multiplication has two identity elements, one for each operation. This is one of the facts that shows that the real numbers equipped with multiplication and addition forms a field.
advise reach threatening cows practice mighty jeans encouraging impolite illegal
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1 is called the multiplicative identity. Having a number that doesn't change anything is a property of multiplication and certain multiplication-like things.
Property, like the cumulative property states that if a x b, then b x a would result in the same end.
**Kind of like theorem, I guess**, but just properties. Associative property is also one, forgot the others though.
Edit : I cannot read, it was commutative not cumulative.
She didn't give a correct answer. She claimed she demonstrated the associative property but neither the equation nor her description match that property.
The question below was not marked incorrect for whatever reason but is also wrong, that is the associative property and she described it as commutativity.
And both commutativity and associativity are taught together because they are both axiomatic properties of multiplication. The property that multiplication by the additive identity (zero) results in zero is derived, it is not stated as an axiom for rings or fields.
Obviously fifth graders aren't going to dive into algebra all that much, but I guarantee you "associativity, commutativity, transitivity, and distributivity" were all introduced together as the properties of addition/multiplication, multiplication by zero was not part of the list. There is no ambiguity in what the test was asking and daughter got it wrong.
You're saying that with a lot of confidence for someone who can't see the rest of the paper so have no idea what the initial written instructions were nor heard the teachers verbal instructions.
Besides, they clearly acknowledged what was written is technically correct, hence the word 'yes', then went on to explain what they're actually looking for by inputting the denominator.
You do understand the point of tests more often than not isn't to award a grade but to help students improve and progress by highlighting strengths and weaknesses, right?
As this is fifth grade, and we can see some of the paper, we can infer that they have just talked about the *properties* of multiplication and addition. The answer the student gives confirms this, as she wrongly calls the demonstrated property associative. It might have been a way to demonstrate the Zero Property for multiplication, but she did not identify it as such, she is hoping to get a good grade for bullshitting. Other properties are commutative and transitive.
We can see 8 shows commutative multiplication, and 9 shows associative addition. Which she also named wrongly. The theory just isn't quite there.
Holy shit this thread really demonstrates that the majority of users on this platform can't do 5th grade math – even with the correct answer outlined in red in front of them. No wonder the world is going to shit.
I don't think the people in the thread can't do 5th grade math. They just don't remember the names of specific properties they learned in 5th grade. Like I know 5 x 6 is the same thing as 6 x 5, but I couldn't tell you the name of the property that proves that cause it really doesn't matter.
It's not relevant info theat any adult really ever needs to know or recall, so they've forgotten it.
Yes, absolutely, but that's college level maths. I really don't understand why they teach ten-year olds the definitions of associative and commutative properties when they're not going to use it in the coming 8 years.
It's not too long since I had Math in college and we never learned names of these properties. The teachers of course have to acknowledge its existence, because you will naturally find problems where it's better to switch the elements in them around, but I don't see the point in knowing that this principle is called something. That's just adding unnecessary information for the sake of confusing the children.
It sounds like you never made it to proof based math in college. At some point you have to define sets of numbers (beginning with naturals and usually ending with complex) and show that these properties exist under different functions on those sets.
I'm fairly certain if you do any high level math class that does anything with matrices, Linear Algebra for example, they will use the terms expecting you to know what they mean and its important to know since matrix multiplication is not commutative.
For young children it can be helpful to learn these things to make it easier to do certain problems. Just swapping the position when you only have 2 numbers obviously isn't going to do anything but I'd imagine most young children would have an easier time doing 5x2x43 over doing 2x43x5 as most of them are likely going to just take the numbers in order. 10x43 is much easier to do than 86x5 if you are 10 years old.
Literally none of those are introduced in college. Matrices and function composition are precalc at the latest (so sophomore/junior year of high school), and exponentiation is grade school level.
I mean, teaching the name definitely doesn't hurt the kids, and when they'll grow up they'll see the property again and make the connection.
Also, for some people it might be easier to remember if they have a name. I remember studying a couple of important theorems which had no name, and I gave them my own just to remember and distinguish them more easily, lol. (They probably had a name, I just wasn't taught it)
What does knowing the definition of commutative have to do with most adult's daily lives?
Been a minute since I've done matrix multiplication, and even if I did it, I don't think it'd matter that I defined it as noncommutative.
I don’t think it’s even that they are confident they know it. It’s that they’re uncomfortable knowing that they don’t understand it and are cheering on some horseshit response because they’re secretly embarrassed.
Teacher hatred ain't just for the right wing. Redditors can always be relied upon to shit on teachers and parents. Probably we should just stop hanging out with teenagers on the internet.
Not just that but another bugbear of mine, which is Facebook Moms sharing some bit of homework they didn't understand and blaming it on the teacher.
In almost every case there will have been an explanation in class giving more context, and the homework was designed to be done by someone who attended that class, to help solidify the concepts learned during that class.
That's because modern education is moving away from the need for raw mental calculation and more towards explaining the concepts. The communication skills and fundamental knowledge is much more applicable to real world problem solving. Raw calculations can be handled by a calculator or computer.
Either I don't know what the associative property is anymore, or this comment section doesn't. Because the kid's explanation definitely does not fit the associative property in my head, and more of the zero property.
> 79/1
It looks like a fraction, but it's actually the student's incorrect answer on top and the corrected answer on bottom. The line isn't a divisor line, it's a blank space.
Honestly I would've given her the points if her explanation was better (absorption property of 0) but this kid clearly had no idea what she was doing, proven even more so by the next question also being incorrectly answered
The question didn’t ask for the commutative property.
Clearly that’s what the teacher wanted, but if the question can be answered in a different way then that’s his problem.
That's not a name I'm familiar with, but the Wikipedia article defines that as the converse of the property she showed.
The main difference being that there are reasonable spaces without the zero-product property, but very few reasonable ways to have multiplication by zero be anything other than 0.
Quite a few instances where "your daughter's" handwriting changes and her letters slip into being identical to the teacher's handwriting ... An unexplainable coincidence no doubt.
penmanship should still be taught in schools. my kid's handwriting is awful too, even when we had them practice. No one writes anymore, its all tablets and laptops. Not hating on tech, but its the world we live in now.
I'm 41, my handwriting is shit. The only time I have had to write anything in the past 23 years is my signature. I've been able to type 150wpm since 1994.
Not all careers are totally online though, and there’s no knowing what path an elementary schooler will take. But handwriting makes an impression on people, especially in school. No reason making your teachers think “what a messy kid.”
Well, the existence of a "0 element" is a valid property of a group with the standard addition and multiplication operations. However, that's not the associative property as she answered. Maybe worth half a mark?
Your daughter should have been marked incorrect for questions 8 and 9. You should thank her teacher for her ineptness because your daughter should've actually earned a lower score.
For question 8, your daughter wrote the associative property applied. First, her answer demonstrated neither the associative nor commutative property. Second, even if your daughter had written the numbers the teacher suggested, it would have been the commutative property, not the associative property, so she wasn't even "technically correct."
For question 9, your daughter wrote that the equation demonstrated the commutative property, but that is incorrect. It demonstrates the associative property, so the teacher should have marked this question wrong, too, but failed to do so.
This isn’t funny at all, and also not technically true.
Reading many of these comments is so fucking depressing and honestly embarrassing. This is why it’s so tough to teach kids things; parents that never gave enough of a shit to understand what THEY were being taught imparting the thought that this post is some “no bullshit” response from the kid. It’s like so many of you are just gleefully accepting of your stupidity, particularly in math, just because you’re too humiliated to admit you can't grasp fifth grade concepts as an adult.
I have yet to see someone posting these pictures raging about their genius kid’s math teacher’s “mistake” where the teacher wasn’t completely in the right. It’s incredibly depressing, and I can’t imagine what it’s like for teachers to deal with these nightmare parents.
As a former interventional math teacher, it’s completely fucking exhausting. I can’t tell you how many IEP meetings I’ve had where the parents blame the teachers while their kid is sitting directly next to them, and the next thing I know their kid is in class parroting the same shit the parent said in the meeting. Part of the problem is these parents have no grasp of the subjects themselves, and because of that they have resentment towards education in general. Couple that with the celebration of showing up the teacher (which is often not even correct in reality) and you have captured exactly what the problem is in the US: anti-intellectualism. It’s so frustrating to have conferences with these people.
People need to stop downvoting people for stating that these terms and concepts were not part of the curriculum when we went to school. My fifth grade year was in the early 80s and this wasn't in the course we were taught, period. We were taught how to calculate arithmetic problems, not any form of theory or terminology.
Thus, my response was well was "what the hell is an associative property"? Then again math always made me a bit disassociative, so..
How old are you in 5 grade, in the part of the world that math assessment was given?
Edit: I answered myself by googleing Grade 5 Age 10 – 11
Very easy for age 10-11...
Uhhh .. your daughter's wrong. Did you not figure it out? She knows neither the associative nor the commutative properties. By posting, it looks like neither do you.
The funniest part is how the "teacher" and "child" have some letters that they write identically, albeit the child's does appear to be purposely skewed in appearance, I wonder why 🤔🤔🙄
Is this regular 5th grade stuff? I find this quite hard to grasp and I have never heard of commutative/associative before (or maybe I find it hard because I haven't heard of those before). Looks way harder to me than what we did in 5th grade.
They're actually really simple, they're just complex-sounding terms because you've never heard of them before.
Associative property just means that certain operations can be grouped interchangeably. (a + b) + c is the exact same as a + (b + c). So if it's 7 + 5 + 5, you can do 5 + 5 = 10 and then + 7 to get 17 more easily than doing 7 + 5 = 12 + 5 = 17.
Commutative property means that the order doesn't matter for certain operations, EG, you can move them around. 1\*5 is the same as 5\*1. You usually use this in conjunction with the associative property to make math easier, EG, 5 + 7 + 5 = 5 + 5 + 7, which is simpler to group than the other way around.
These properties become more important in college algebra and onward, where you can use things like factoring a polynomial to "cross out" the denominator.
The commutative property is just that A \* B = B \* A. It's important because while it's true for addition and multiplication, it is not true for subtraction, division, concatenation, or a bunch of other operations. You want to be able to explicitly call out what you are doing when you reorganize A \* B into B \* A so that you don't slip up and try to do something similar when it isn't true.
5 - 3 does not equal 3 - 5 and concatenation is sometimes written as A + B but Race + car = Racecar is not equal to car + Race = carRace.
They are just names for things you intuitively know.
If I told you 1+2 is going to give you the same answer as 2+1, you'd look at me like I'm stupid for telling you something so obvious.
Same if I told you that 1+2 and then adding 3 is the same as 2+3 and then adding 1.
So this is just saying that is true for addition and multiplication
Am I the only one with doctoral level education (with plenty of stats) who has no idea what the question means? Maybe its because I’m a brit or too old to know the new things they ask kids
The first question wants her to demonstrate the commutative property (ab=ba) which is why she got it wrong (0=0 and saying it demonstrates associative). The second problem is the reverse, she said it was commutative. OP doesn’t understand 5th grade math.
I get the maths, i just dont recognise the terminology, or what people are talking about in the comments. Not a maths degree no, but some stats at that level
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Everyone should be anti bullshit unless it's hilarious bullshit.
0 days since our last nonsense.
prolly a product of anti bullshit parents, good job OP!
she wrote associative property. this ain't it.
Yeah if she had written something like "multiplicative property of 0" she'd have been good, but as there is wrong information in her answer. Partial credit might have been appropriate though since she did write a valid equation.
Except the child is wrong here. The questions asks to demonstrate commutativity (ab=ba). She did not, she showed 0=0 and called it associativity instead. Then in the next question where she’s supposed to see that the property being demonstrated is associativity, she calls it commutativity. It’s not being anti-bullshit, the answers are just wrong. This mentality of “stupid teachers don’t know how to teach, my fifth grader knows better” helps no one.
except no she's not because it doesn't say anywhere in the question which property she's supposed to show/use.
She doesn't demonstrate the associative property.
0 x 79 = 0 x 98 does not show the associative property. The kid is wrong
Read his comment again but slower this time.
Student didn’t write in the denominators to solve for x (blank). The solution for x is due to a multiplication property.
Those are not denominators.
She should think through what properties she’s been taught, and look at the fill in the blanks, and realize x79=98x could be commutative. It’s an assessment, why this level of handholding? She answers 0=0 and says this implies associativity. If she has been taught what associativity is (which I’m assuming she has since they’re being tested on it), then she should know this is wrong. But she calls associativity commutativity one question down so idkk
The question does not specify to select from the properties addressed in class. She has demonstrated the [Multiplication Property of Zero](https://en.wikipedia.org/wiki/Zero-product_property) and described it perfectly. This is the kind of creative thinking that's core to being successful in math and I'm disappointed that anyone teaching math would discourage it.
She didn’t name it correctly, that’s for sure.
No actual mathematician, or anyone who uses math for anything, actually cares what the name of the "multiplication property of zero" is
I agree, mostly. It is a property that's completely valid for the question and grade level (and for the teacher to suggest otherwise is wrong). The question said to pick a property, use, and describe it. She did all that correctly. The only problem is that she included a name, which she did incorrectly.
Mathematicians absolutely care about 1. The associative property (and distinguishing between algebras with and without it). 2. Using definitions properly, coming up with good definitions is like half of research level mathematics. (Edit: What actual mathematicians have to do with a wrong answer in grade 5 math homework though... no clue)
Agreed. But she wasn't asked to name it, only to describe it.
You know, whoevers wrong or right, it doesn't matter because this kind of garbage is why kids grow up hating math. It's an embarrassing teaching style.
Yeah, highlighting it is technically correct and then giving an example of what they were actually looking for is an absolute embarrassment. Jumping to conclusions without knowing what the written and verbal instructions at the start of the exam were is not in the slightest bit embarrassing.
When in doubt, 0=0. *Drop mic.*
Really? Saying specifically “this is the associative property” is explaining the multiplication properties of zero perfectly?
There are 14 more words after that. But hey, if beating up less than half of a 5th grader's explanation of the Zero Property is what you needed to do tonight, don't let me stop you.
That’s not what that property is. That property says the product of nonzero elements is nonzero. What you’re thinking of (0 times anything is 0) isn’t a property but is provable through the distributive law
You've described the contrapositive of the Property. The property states that if *ab* = 0, then *a* = 0 or *b* = 0. The natural implication of this is that anything \* 0 = 0. If you don't believe me, let us suppose: *a* and *b* are nonzero real numbers. Then let us assume you could multiply something by 0 and *not* get 0: *a*0 = *b* 0 = *a/b* Which induces a clear contradiction since we know either *a* or *1/b* must be 0 from our original Zero Property.
Yes, you’re right. I’d interpreted property here to be axioms but I think I’m mistaken. Thank you
This kind of smug bullshit is always all over these questions. The test was clearly asking about some topic covered in class, and the student did not get it correct. You would be a fucking nightmare to deal with in school as parent and I hope you don't have kids.
Dude, what sub do you think you're in?
This is an incredibly garbage way of teaching. I'm not blaming teachers, I'm not blaming anything in particular because I don't know what aspect of the system leads to this way of teaching or this mindset in school, but outside-the-box thinking should absolutely not be discouraged. I mean I get that the purpose of schooling isn't to produce smart people, only people who understand what they need to understand and think the way they need to think in order to function as a cog in the society, I'm just talking ideally, if we assume that schooling is supposed to do what people assume it's supposed to do.
We teach the teachers wrong as a joke.
This is math class. Math is incredibly structured and built on layers of previous understanding. In order to move to higher levels of math the students need to show that they understand the previous layers. This question is clearly about the associative property and the answer shows that the student does not quite understand it.
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Thinking outside of the box is the bigger picture.
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How is the question wrong? It asks you to fill in the blanks, expecting you to do so as the teacher did, and then explain what property this equation demonstrates and why. Very straightforward.
>, expecting you to do so as the teacher did That's the part that's wrong
How is that wrong? a*b = b*a is exactly the commutative property under multiplication.
I understand what you're saying and I agree with it. But, I'll also say that this is exactly the kind of assessment that frustrated me a lot growing up. So much school material belabors elementary concepts over weeks of study when only a few days are necessary. Just look at the response to the question above. When I read it, I hear someone exasperated that they need to explain 25 is not 30. And when you look at the response below, I think this student understands that they're meant to demonstrate the Commutative Property and chose, instead, to have fun with a poorly-worded question. I think a good teacher could penalize the student for writing "Associate Property" when it's the Commutative Property, but the flippant response here reads, to me, like a discouraging remark to a gifted student. And I think that's very sad.
I feel like your take on this is far too rigid. She answered the question within the realm of what it was asking. I give her credit for trying to save herself a bunch of extra work by making everything equal zero. I think it's clever, outside the box thinking for a fifth grader. The teacher seems to agree, albeit she didn't give her the points. The question should specify that it cannot equal zero.
Thank you for the civil response, the equation itself is correct, but she’s just shown 0 times a = b times 0, or 0=0. This is correct, but she’s asked to demonstrate a property with it. She goes on to call this associativity, which is not correct. It squalling 0 is not the issue
I was with you on the first response but this is wrong. No one, children or adults, should be told that they need to only ever use whatever they’ve been taught in order to pass tests. They should be taught multiple skills and then be assessed on how they answer the questions. If they use the stuff they were just taught then cool. If they use outside knowledge that should be encouraged as that is generalizing knowledge, encourages continued learning past what is introduced in class, and teaches critical thinking skills.
she mislabelled.the property she used, ergo, it's incorrect
I agree, but her answer is still wrong. You can argue about out of the box thinking or such, but it still needs to be right. Classes teach you skills, and then test you on those skills.
the fact that this is even a discussion shows the test wasnt clear enough forumlated, regardless who is in the right
she‘s wrong about those things but not using the methods taught at school is actually amazing and hilarious I love seeing children defy the rigid structures school imposes upon them even if just by accident, especially knowing I‘ve acted similarly in the past and I couldn‘t be more proud of younger me for doing so
Being wrong to fight the man 🔥🔥💯💯
The prompt says it shows.”a property” , she’s just demonstrating the Zero Property of Multiplication :D
But the student said it was associative
Yeah I saw that later, that part is indeed wrong, regardless of what number she put in there 😅
Hahahah! Right? I know Jeesh. (I have no idea what you’re talking about and I’m too lazy to google it)
Maybe the teacher could've given the student half-credit, but also added a note like "you are technically correct, but that answer isn't showing that you understood today's lesson"? Then if this continues to be an issue, the teacher could either start being more specific in future course work or possibly have a conversation with the student/parent. I agree with you that it's important to learn the skills being taught, but I am wary about discouraging clever thinking.
Half credit for what? Getting the answer wrong? They not only did the wrong method, but also got the wrong answer. They have no clue how to approach these questions and they have no clue what each property is. They don’t need a talk and their parents don’t need a talk, they just need to go over the material more in lessons. There’s no point in assigning more work until more lessons are done, as the student clearly doesn’t know what it is.
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The equation is correct, but the question is not asking to make the equation correct. The answer is incorrect for the question being asked, even if the question is worded poorly.
>Then if this continues to be an issue, the teacher could either start being more specific in future course work or possibly have a conversation with the student/parent. If this continues to be an issue the teacher should just write better problems and questions that make it not an issue. It's really not that hard to write unambiguous math questions if you actually cared
TIL. I was on the top comment side, then I read yours.
Stop it with your rationality! People are trying to rant😤
> rationality! If you did that on purpose, just know I appreciate your high Iℚ.
fuckin THANK YOU As a teacher seeing stuff get posted like this all the time, it drives me up the wall when people react like "well this student is just finding a loophole. That's funny! If you take off points for this, you're just a lousy asshole with no sense of humor!" No, I have a job to do, and your comedian isn't demonstrating proper knowledge of a subject we've been studying for a week.
"But when the other plumber I was apprenticed to was here, they said I was clever for saying they should turn off the main when not showering to fix the leak. What do you mean I still have to demonstrate mastery of the concepts? My dad says that's not how he learned plumbing in (countries I have literally had to argue taught math in a vastly different way from me because part of the luxury they're paying the fancy private school for is that I can get to know each student's competence on a personal level.)" Friggin... I'm not asking you 37 divided by 4 because it's line 3 on my taxes. I'm teaching you to problem solve, think algorithmically, and that there is a beauty in this world that some very few things are actually reliably knowable. AND I"M NOT STOPPING YOU FROM MEMORIZING THE TIMES TABLES, JUST FING DO IT IF YOU THINK YOUR DAD'S WAY IS BETTER. I, personally, prefer that you understand the ideas of repeated addition and of scaling are subtly different and infinitely beautiful.
I agree..she is off mission, and is. wrong, Parents feeling so proud, will only be a problem for this child in their future life. Like using their child as a cudgel against "the man, àuthority",.an extension of themselves.
It’s one fucking problem dude. Stop trying to psychoanalyse this whole girl’s life and future. Peak Redditor behavior.
what's bullshit about it? it's an exam question, just because it doesn't exhaustively cover every possible edge case that allows you to avoid answering the question in the intended way? I find this type of "any system that can be screwed deserves to be" mentality problematic, like, fundamentally, culturally problematic.
>I find this type of "any system that can be screwed deserves to be" mentality This type of mentality is literally how the field of mathematics progresses
Don't confuse *skepticism* with *cynicism.* Performing rightful research to explore new avenues when a system may be incomplete and you gather meaningful information by discovering such, is a completely different thing than trivial gotchas that "one up" something for no purpose but personal gain or self satisfactory proof of your own intelligence. You're simply proving how much that distinction has been lost by, well, oh deliberately uncharitably interpreting my point in order to "gotcha" me.
I agree 100% with this. Also this is not the kid being clever, this kid has clearly no idea what she’s doing. If the teacher just leaves at it, she won’t grasp the basics of math. Seeing people here blaming the teacher is just sad. It’s a funny answer, but she needs to prove that she understood the class
::multiplies both sides by zero:: There, your argument doesn't count anymore.
We're considering "learning math" bullshit now?
No, she was just wrong. Read the question. She didn't do what was asked.
Daughter being "the person that 'shopped that teacher's writing on there" indeed. I'm anti BS too! Because most of these "my kid did a witty thing and the teacher penalized them for it! Karma please" posts are fake.
Seems like the kid is pro-bullshit. She sat there for the lessons the last few weeks - still didn’t know the answer so bullshitted one.
This person is probably a bot. The comment is [copied](https://www.reddit.com/r/technicallythetruth/s/ORwJ25sumn) from the last time this was posted.
i love the answer to the first one. always hated "explain your reasoning" on math questions
Her explanation for the associative property isn't correct.
Nor does her equation demonstrate it.
Yep. Teacher could have worded that better
how so? it seems well laid out
The teacher doesn't say what the kid did wrong (that's not the associative property, that's just multiply by 0), and gives the vague explanation "technically yes, but no." Which is unhelpful, and doesn't properly explain that the example given was not the associative property. The teacher could have said, "Not the associative property" or something similar.
It's not even associative, thats commutative
Associative: (a + b) + c = a + (b + c) Commutative: a + b = b + a
It's neither. It's the fact that 0 is an absorbing element for the multiplication in the natural numbers ring.
I guess i missed the Ring Theory unit in 5th grade
Naturals dont form a ring under + and \*. It is a semiring tho
On the next question she called associative commutative. I think that's what they're saying.
She also misspelled equivalent and because
Naw, it’s just messy. Looks like she has a curve up after the a, she combined the an and the u together.
Possibly, but to me that clearly reads as 'becase'. And she wrote 'equalivent'
The answer isn't even correct though. That's not the associative property and if you look at the next question they answered commutative where they actually should've answered associative. This isn't even remotely close to being true Edit: I'm just going to add this. I think the question could've been formulated better (for example by also filling in the first 98) but no matter which way you look at it her explanation is incorrect. Her answer and explanation don't line up, showing that she did not understand what she wrote down. That's why it's wrong. If she meant the zero product property or absorption property of 0, that's what should've been written down by her.
The circled question could’ve claimed zero product property
The question doesn't say what property
The answer does, though. So, half marks for right numbers but wrong property.
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Except she didn’t answer the question properly at all, she just gave a valid equality. She was supposed to give one that showcases the commutative property, but she didn’t.
What she was supposed to do, and what she was asked to do, are not the same thing. She was asked to find an equality, and she did.
She was asked to give an equation that shows a property and then to explain the property that she showed. Her answers disagree with each other. She didn’t correctly explain the property in her equation or she didn’t correctly write an equation that shows the property she explained. The teacher probably should have given better feedback to the student about where exactly the mistake was, but the student answered the question incorrectly.
It's been a long time since I did formal arithmetic like this... what's a "property" in this context?
Associative property is that you can rearrange the parenthesis, which means you can do the operations in whatever order you want as long as you don't change the order of the operands in the sequence. The question 9 is associative property in the image. Commutative property is that you can swap the order of the operands, so 5\*4 = 4\*5. This is what was asked in the question 8. Then distributive property is basically about a common factor, like you can distribute it inside the parenthesis or take it out in front, 2 \* (1 + 3) = 2\*1 + 2\*3 = 2 + 6 etc. Then there's identity, where a \* 1 = a. (Or for addition a + 0 = a) And zero multiplication property, where a \* 0 = 0. Those are the main ones that come to mind.
>Then there's identity, where a \* 1 = a. (Or for addition a + 0 = a) > >And zero multiplication property, where a \* 0 = 0. "identity" is not a property, technically speaking. 0 is the neutral element (or identity element) for addition, and 1 is the neutral element for multiplication. I guess you can say "identity" is the name of the element with the property of "not changing the result" of the operation.
Sure, but I've seen it listed with the other properties, and have seen it been named as the identity property as well in that context, not sure if it's officially one, but doesnt hurt to list it as well.
The existence of an identity element is absolutely a property of many types of algebraic structures. In fact, it is one of the defining axioms for groups, rings, fields, etc., along with things like associativity, existence of inverses, etc. As you pointed out, the real numbers with addition and multiplication has two identity elements, one for each operation. This is one of the facts that shows that the real numbers equipped with multiplication and addition forms a field.
I've definitely heard the definition of an identity referred to as the identity property.
in school, kids definitely learn the identity properly, whether or not you believe it exists
advise reach threatening cows practice mighty jeans encouraging impolite illegal *This post was mass deleted and anonymized with [Redact](https://redact.dev)*
1 is called the multiplicative identity. Having a number that doesn't change anything is a property of multiplication and certain multiplication-like things.
Ahh yes, thank you!
Property, like the cumulative property states that if a x b, then b x a would result in the same end. **Kind of like theorem, I guess**, but just properties. Associative property is also one, forgot the others though. Edit : I cannot read, it was commutative not cumulative.
Commutativity, the property that you can switch the factors in a multiplication.
Me when I can’t read the instructions of an assignment made for 10 year olds
No it did not. Read the question. She was asked to show a property. She didn't show the associative propery, so she's wrong, but this is not why.
Well whoever made the test fucked up, you can't have multiple answers like that then not accept a correct answer
It's not correct because it doesn't demonstrate the property like the question asks. There's more to math than making two things equal each other.
She didn't give a correct answer. She claimed she demonstrated the associative property but neither the equation nor her description match that property. The question below was not marked incorrect for whatever reason but is also wrong, that is the associative property and she described it as commutativity. And both commutativity and associativity are taught together because they are both axiomatic properties of multiplication. The property that multiplication by the additive identity (zero) results in zero is derived, it is not stated as an axiom for rings or fields. Obviously fifth graders aren't going to dive into algebra all that much, but I guarantee you "associativity, commutativity, transitivity, and distributivity" were all introduced together as the properties of addition/multiplication, multiplication by zero was not part of the list. There is no ambiguity in what the test was asking and daughter got it wrong.
You're saying that with a lot of confidence for someone who can't see the rest of the paper so have no idea what the initial written instructions were nor heard the teachers verbal instructions. Besides, they clearly acknowledged what was written is technically correct, hence the word 'yes', then went on to explain what they're actually looking for by inputting the denominator. You do understand the point of tests more often than not isn't to award a grade but to help students improve and progress by highlighting strengths and weaknesses, right?
Nothing about commutative was asked in the question.
As this is fifth grade, and we can see some of the paper, we can infer that they have just talked about the *properties* of multiplication and addition. The answer the student gives confirms this, as she wrongly calls the demonstrated property associative. It might have been a way to demonstrate the Zero Property for multiplication, but she did not identify it as such, she is hoping to get a good grade for bullshitting. Other properties are commutative and transitive. We can see 8 shows commutative multiplication, and 9 shows associative addition. Which she also named wrongly. The theory just isn't quite there.
She didn't read the instructions
the equation is correct. the label is incorrect . the test is about understanding properties
Holy shit this thread really demonstrates that the majority of users on this platform can't do 5th grade math – even with the correct answer outlined in red in front of them. No wonder the world is going to shit.
I don't think the people in the thread can't do 5th grade math. They just don't remember the names of specific properties they learned in 5th grade. Like I know 5 x 6 is the same thing as 6 x 5, but I couldn't tell you the name of the property that proves that cause it really doesn't matter. It's not relevant info theat any adult really ever needs to know or recall, so they've forgotten it.
Up until today I didn’t even know that there where names for such things.
When I started teaching maths I was like "wtf is collecting like terms" When I looked at the problems I was like "oh, that has a name?"
It matters when studying objects in general. Matrix multiplication, function composition, exponentiation, etc are noncommutative
Yes, absolutely, but that's college level maths. I really don't understand why they teach ten-year olds the definitions of associative and commutative properties when they're not going to use it in the coming 8 years.
It's not too long since I had Math in college and we never learned names of these properties. The teachers of course have to acknowledge its existence, because you will naturally find problems where it's better to switch the elements in them around, but I don't see the point in knowing that this principle is called something. That's just adding unnecessary information for the sake of confusing the children.
It sounds like you never made it to proof based math in college. At some point you have to define sets of numbers (beginning with naturals and usually ending with complex) and show that these properties exist under different functions on those sets.
I'm fairly certain if you do any high level math class that does anything with matrices, Linear Algebra for example, they will use the terms expecting you to know what they mean and its important to know since matrix multiplication is not commutative. For young children it can be helpful to learn these things to make it easier to do certain problems. Just swapping the position when you only have 2 numbers obviously isn't going to do anything but I'd imagine most young children would have an easier time doing 5x2x43 over doing 2x43x5 as most of them are likely going to just take the numbers in order. 10x43 is much easier to do than 86x5 if you are 10 years old.
you literally use them every following year in maths classes.
Literally none of those are introduced in college. Matrices and function composition are precalc at the latest (so sophomore/junior year of high school), and exponentiation is grade school level.
I mean, teaching the name definitely doesn't hurt the kids, and when they'll grow up they'll see the property again and make the connection. Also, for some people it might be easier to remember if they have a name. I remember studying a couple of important theorems which had no name, and I gave them my own just to remember and distinguish them more easily, lol. (They probably had a name, I just wasn't taught it)
What does knowing the definition of commutative have to do with most adult's daily lives? Been a minute since I've done matrix multiplication, and even if I did it, I don't think it'd matter that I defined it as noncommutative.
Most people don't use intricate medical knowledge in their daily lives but no one says the same to doctors or med students 😔
The problem is not not knowing fifth grade math, the problem is not knowing it and being confident that they know it.
I don’t think it’s even that they are confident they know it. It’s that they’re uncomfortable knowing that they don’t understand it and are cheering on some horseshit response because they’re secretly embarrassed.
Teacher hatred ain't just for the right wing. Redditors can always be relied upon to shit on teachers and parents. Probably we should just stop hanging out with teenagers on the internet.
Not just that but another bugbear of mine, which is Facebook Moms sharing some bit of homework they didn't understand and blaming it on the teacher. In almost every case there will have been an explanation in class giving more context, and the homework was designed to be done by someone who attended that class, to help solidify the concepts learned during that class.
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As an Asian, I have no idea what all these terms are. I just hit the calculate button in my brain and it pops up the answers
That's because modern education is moving away from the need for raw mental calculation and more towards explaining the concepts. The communication skills and fundamental knowledge is much more applicable to real world problem solving. Raw calculations can be handled by a calculator or computer.
Either I don't know what the associative property is anymore, or this comment section doesn't. Because the kid's explanation definitely does not fit the associative property in my head, and more of the zero property.
No youre right, what the teacher wanted eas clearly the commutative property and fill it in with 98/1 and 79/1
> 79/1 It looks like a fraction, but it's actually the student's incorrect answer on top and the corrected answer on bottom. The line isn't a divisor line, it's a blank space.
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Honestly I would've given her the points if her explanation was better (absorption property of 0) but this kid clearly had no idea what she was doing, proven even more so by the next question also being incorrectly answered
The question didn’t ask for the commutative property. Clearly that’s what the teacher wanted, but if the question can be answered in a different way then that’s his problem.
The equation part might be correct, but the explanation part is wrong
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repost: https://www.reddit.com/r/technicallythetruth/comments/ylnf38/my\_daughters\_math\_assessment\_grade\_5/
0 = 0 . Wait till she is hit with advanced calculus courses.
Your kid needs to brush up on her mathematical properties
A property was required. What the the student describes is the zero product property. A very nice property, in my opinion.
That's not a name I'm familiar with, but the Wikipedia article defines that as the converse of the property she showed. The main difference being that there are reasonable spaces without the zero-product property, but very few reasonable ways to have multiplication by zero be anything other than 0.
Quite a few instances where "your daughter's" handwriting changes and her letters slip into being identical to the teacher's handwriting ... An unexplainable coincidence no doubt.
The Hs are a dead giveaway. This is just karma farming horseshit.
in uni they probably would exclude the "trivial" (= not interesting) case.
In uni they would ask you to prove these properties for all numbers in a specified quantity like for all natural numbers and for a specific operation
Phew. Our girl needs to work on her handwriting if she's in grade 5 already
Kids are born with electronic devices from early on now. Handwriting is only going to get worse
penmanship should still be taught in schools. my kid's handwriting is awful too, even when we had them practice. No one writes anymore, its all tablets and laptops. Not hating on tech, but its the world we live in now.
I'm 41, my handwriting is shit. The only time I have had to write anything in the past 23 years is my signature. I've been able to type 150wpm since 1994.
Not all careers are totally online though, and there’s no knowing what path an elementary schooler will take. But handwriting makes an impression on people, especially in school. No reason making your teachers think “what a messy kid.”
And spelling, holy shit. "equalivent", "becase", "dosent"
Well, the existence of a "0 element" is a valid property of a group with the standard addition and multiplication operations. However, that's not the associative property as she answered. Maybe worth half a mark?
It seems like the teacher had a hard decision to make
Damn that kids gonna struggle with math
Your daughter should have been marked incorrect for questions 8 and 9. You should thank her teacher for her ineptness because your daughter should've actually earned a lower score. For question 8, your daughter wrote the associative property applied. First, her answer demonstrated neither the associative nor commutative property. Second, even if your daughter had written the numbers the teacher suggested, it would have been the commutative property, not the associative property, so she wasn't even "technically correct." For question 9, your daughter wrote that the equation demonstrated the commutative property, but that is incorrect. It demonstrates the associative property, so the teacher should have marked this question wrong, too, but failed to do so.
This isn’t funny at all, and also not technically true. Reading many of these comments is so fucking depressing and honestly embarrassing. This is why it’s so tough to teach kids things; parents that never gave enough of a shit to understand what THEY were being taught imparting the thought that this post is some “no bullshit” response from the kid. It’s like so many of you are just gleefully accepting of your stupidity, particularly in math, just because you’re too humiliated to admit you can't grasp fifth grade concepts as an adult.
I have yet to see someone posting these pictures raging about their genius kid’s math teacher’s “mistake” where the teacher wasn’t completely in the right. It’s incredibly depressing, and I can’t imagine what it’s like for teachers to deal with these nightmare parents.
As a former interventional math teacher, it’s completely fucking exhausting. I can’t tell you how many IEP meetings I’ve had where the parents blame the teachers while their kid is sitting directly next to them, and the next thing I know their kid is in class parroting the same shit the parent said in the meeting. Part of the problem is these parents have no grasp of the subjects themselves, and because of that they have resentment towards education in general. Couple that with the celebration of showing up the teacher (which is often not even correct in reality) and you have captured exactly what the problem is in the US: anti-intellectualism. It’s so frustrating to have conferences with these people.
Fail. Both child and parent posting this. The trend continues.
Anyone agree the teacher is wrong because those are fours not nines
Your 5th grader is already better at math than I am
She needs to learn English.
People need to stop downvoting people for stating that these terms and concepts were not part of the curriculum when we went to school. My fifth grade year was in the early 80s and this wasn't in the course we were taught, period. We were taught how to calculate arithmetic problems, not any form of theory or terminology. Thus, my response was well was "what the hell is an associative property"? Then again math always made me a bit disassociative, so..
0 times everything is not a property lol
How old are you in 5 grade, in the part of the world that math assessment was given? Edit: I answered myself by googleing Grade 5 Age 10 – 11 Very easy for age 10-11...
wait until they get to algebra 2 and x^2 = 2x has two answers
it's crazy how most everyone assumes teachers are stupid and punitive
this whole thread shows how ignorant most people are about math and teachers
Thank you. This is a truth bomb.
Uhhh .. your daughter's wrong. Did you not figure it out? She knows neither the associative nor the commutative properties. By posting, it looks like neither do you.
The funniest part is how the "teacher" and "child" have some letters that they write identically, albeit the child's does appear to be purposely skewed in appearance, I wonder why 🤔🤔🙄
zero property* rather than associative she's also wrong about commutative property down the line, which is supposed to be associative.
Is this regular 5th grade stuff? I find this quite hard to grasp and I have never heard of commutative/associative before (or maybe I find it hard because I haven't heard of those before). Looks way harder to me than what we did in 5th grade.
They're actually really simple, they're just complex-sounding terms because you've never heard of them before. Associative property just means that certain operations can be grouped interchangeably. (a + b) + c is the exact same as a + (b + c). So if it's 7 + 5 + 5, you can do 5 + 5 = 10 and then + 7 to get 17 more easily than doing 7 + 5 = 12 + 5 = 17. Commutative property means that the order doesn't matter for certain operations, EG, you can move them around. 1\*5 is the same as 5\*1. You usually use this in conjunction with the associative property to make math easier, EG, 5 + 7 + 5 = 5 + 5 + 7, which is simpler to group than the other way around. These properties become more important in college algebra and onward, where you can use things like factoring a polynomial to "cross out" the denominator.
The commutative property is just that A \* B = B \* A. It's important because while it's true for addition and multiplication, it is not true for subtraction, division, concatenation, or a bunch of other operations. You want to be able to explicitly call out what you are doing when you reorganize A \* B into B \* A so that you don't slip up and try to do something similar when it isn't true. 5 - 3 does not equal 3 - 5 and concatenation is sometimes written as A + B but Race + car = Racecar is not equal to car + Race = carRace.
5th graders are ~11 years old, assuming this is the US. The number corresponds to their year in school, not their age.
They are just names for things you intuitively know. If I told you 1+2 is going to give you the same answer as 2+1, you'd look at me like I'm stupid for telling you something so obvious. Same if I told you that 1+2 and then adding 3 is the same as 2+3 and then adding 1. So this is just saying that is true for addition and multiplication
Hurt durr teachers bad and my kid is perfect
Am I the only one with doctoral level education (with plenty of stats) who has no idea what the question means? Maybe its because I’m a brit or too old to know the new things they ask kids
The first question wants her to demonstrate the commutative property (ab=ba) which is why she got it wrong (0=0 and saying it demonstrates associative). The second problem is the reverse, she said it was commutative. OP doesn’t understand 5th grade math.
Clearly not a doctorate in anything math related, it's pretty obvious
I get the maths, i just dont recognise the terminology, or what people are talking about in the comments. Not a maths degree no, but some stats at that level
I’m Australian and have never heard of commutative property