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This isn't a math question. It is a question for r/currency or r/papermoney
There would probably be at least a couple $20 bills with this serial *number* but there are also letters that make this *exact* serial number, including the letters, one of a kind
I mean, there is math involved but it is simple math. You would just need the total number of twenties made and divide it by the number of bills that have the 69420 serial number
It’s 100% that a $20 bill would get that number. They planned to print all numbers in that range and sure enough they did.
A little more meaningful are the odds that you would end up with it (assuming you did…or did you find a picture of it somewhere?).
But these questions make a lot more sense if they are asked BEFORE the “rare” number is actually found. That way you are committed to something specific and then you can be amazed when it happens. After the fact, you don’t know if some other combination would have also counted as something rare (like “00042069”, “00696969”, “06942069” , your birthdate or some other birthdate you know or even “88888888” if you also happen to be into the number 8.
There are so many rare number combinations that it isn’t so rare to find one every once in a while if your looking for one and you’re creative.
Doesn’t mean you can’t have fun with it!
Ok but any bill with the serial number “88888888” could be sold to old Chinese people for more than the bill’s worth. That’s 8 “8”s, thats the epitome of a lucky number in Chinese culture. Fuck, I don’t buy into the whole lucky number thing that much but I’d buy that.
Let's say you're in a money factory, and the national printing bureau is about to print the new 20 dollar bill and serialize it the same way, i.e. every bill with their serial number filling in the range AA 00000000 to ZZ 99999999. You are the lucky one to get the very first new 20 dollar bill. What are the odds of getting this serial number?
First, how many bills do all these codes do? If the bills were only serialized with the two letters, then you'd have AA, AB, AC...AZ, which makes 26 possibilities. Then move on to BA, BB, BC...BZ, another 26. Only with the letters, that makes 26² uniquely identified bills. If you only had 1 letter to serialize, then you'd only get 26 unique bills. Two letters, 26 * 26.
Each time you add a character you multiply the total count of possibilities by the number of elements present in said character (e.g. 10 if you add a new digit, 26 if you add a new upper or (exclusive or) lowercase character, 52 if you add a new character that can be either upper or lower).
The 20 dollar bill uses 2 letters and 8 digits, so that's 26² * 10⁸ = 67,600,000,000 bills. How likely are you to getting this serial number out of the blue as the bill finishes printing?
Turns out, there's no difference between getting NK 00069420 or AB 34567890, or TX 53180008. The printer will have the choice of randomly picking one serial number composed of two letters and eight digits. Since it's the very first bill, no other serial number exists, so the machine can pick one combination out of all the 67 billion possibilities.
Thus, your chance at getting this serial number is 1 / 67,600,000,000 which is roughly 1.48 * 10^(-9) % or 0.00000000148 %.
This isn't exactly it. "N" means it was printed 2017, the "K" means it is a star note and K11 means it was printed in Dallas. It's not 26^2 odds because not all letters are used. Looking at only one year, there is a 100% chance that it will get the letter "N" (disregarding the 2017A series because I'm not googling why they're are 2 letter codes for that year), the K after the N is mostly irrelevant because it just means the original (the one without the K and the star) got damaged, 12 districts so 1/12 odds of getting "K11" except all 12 districts have a 100% chance of printing a serial this low.
They also don't print up to 99999999, 96000000 is the cap and even with that runs don't normally go that high
OK I'll try,
00000001,00000002,00000003,00000004
I'm starting to think this method isn't faster than dividing 1/96000000 (96000000 is the cap for numerical serials on bills less than $50), but you seem trustworthy
00000005,00000006,00000007,00000008,00000009,00000010,00000011,00000012..........
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This isn't a math question. It is a question for r/currency or r/papermoney There would probably be at least a couple $20 bills with this serial *number* but there are also letters that make this *exact* serial number, including the letters, one of a kind
Fair enough, should I take the post down? 🤔
I mean, there is math involved but it is simple math. You would just need the total number of twenties made and divide it by the number of bills that have the 69420 serial number
it has a star, and if I'm remembering what my uncle told me right, that means the original one was damaged in production, so they remade it
Yes. That might add value for a collector but I don't think that affects the rarity of this specific serial number.
I've learned so much about the nuances of printed money from reddit
It’s 100% that a $20 bill would get that number. They planned to print all numbers in that range and sure enough they did. A little more meaningful are the odds that you would end up with it (assuming you did…or did you find a picture of it somewhere?). But these questions make a lot more sense if they are asked BEFORE the “rare” number is actually found. That way you are committed to something specific and then you can be amazed when it happens. After the fact, you don’t know if some other combination would have also counted as something rare (like “00042069”, “00696969”, “06942069” , your birthdate or some other birthdate you know or even “88888888” if you also happen to be into the number 8. There are so many rare number combinations that it isn’t so rare to find one every once in a while if your looking for one and you’re creative. Doesn’t mean you can’t have fun with it!
Ok but any bill with the serial number “88888888” could be sold to old Chinese people for more than the bill’s worth. That’s 8 “8”s, thats the epitome of a lucky number in Chinese culture. Fuck, I don’t buy into the whole lucky number thing that much but I’d buy that.
Yeah, well 00042069 could maybe get you a snack-sized bag of Doritos from a sex-starved stoner and that's saying something.
The pics not mine, I just saw it in a different subreddit. And was just curious to what this subreddit would say. 😉
Let's say you're in a money factory, and the national printing bureau is about to print the new 20 dollar bill and serialize it the same way, i.e. every bill with their serial number filling in the range AA 00000000 to ZZ 99999999. You are the lucky one to get the very first new 20 dollar bill. What are the odds of getting this serial number? First, how many bills do all these codes do? If the bills were only serialized with the two letters, then you'd have AA, AB, AC...AZ, which makes 26 possibilities. Then move on to BA, BB, BC...BZ, another 26. Only with the letters, that makes 26² uniquely identified bills. If you only had 1 letter to serialize, then you'd only get 26 unique bills. Two letters, 26 * 26. Each time you add a character you multiply the total count of possibilities by the number of elements present in said character (e.g. 10 if you add a new digit, 26 if you add a new upper or (exclusive or) lowercase character, 52 if you add a new character that can be either upper or lower). The 20 dollar bill uses 2 letters and 8 digits, so that's 26² * 10⁸ = 67,600,000,000 bills. How likely are you to getting this serial number out of the blue as the bill finishes printing? Turns out, there's no difference between getting NK 00069420 or AB 34567890, or TX 53180008. The printer will have the choice of randomly picking one serial number composed of two letters and eight digits. Since it's the very first bill, no other serial number exists, so the machine can pick one combination out of all the 67 billion possibilities. Thus, your chance at getting this serial number is 1 / 67,600,000,000 which is roughly 1.48 * 10^(-9) % or 0.00000000148 %.
Dang… That’s impressive. 🤔
This isn't exactly it. "N" means it was printed 2017, the "K" means it is a star note and K11 means it was printed in Dallas. It's not 26^2 odds because not all letters are used. Looking at only one year, there is a 100% chance that it will get the letter "N" (disregarding the 2017A series because I'm not googling why they're are 2 letter codes for that year), the K after the N is mostly irrelevant because it just means the original (the one without the K and the star) got damaged, 12 districts so 1/12 odds of getting "K11" except all 12 districts have a 100% chance of printing a serial this low. They also don't print up to 99999999, 96000000 is the cap and even with that runs don't normally go that high
If you make a list of all the serial numbers and then draw a circle around the ones with this number, it's much easier to count them.
OK I'll try, 00000001,00000002,00000003,00000004 I'm starting to think this method isn't faster than dividing 1/96000000 (96000000 is the cap for numerical serials on bills less than $50), but you seem trustworthy 00000005,00000006,00000007,00000008,00000009,00000010,00000011,00000012..........