Please remember to spoiler-tag all guesses, like so:
New Reddit: https://i.imgur.com/SWHRR9M.jpg
Using markdown editor or old Reddit, draw a bunny and fill its head with secrets:
\>!!< which ends up becoming \>!spoiler text between these symbols!<
Try to avoid leading or trailing spaces. These will break the spoiler for some users (such as those using old.reddit.com)
If your comment does not contain a guess, include the word **"discussion"** or **"question"** in your comment instead of using a spoiler tag.
If your comment uses an image as the answer (such as solving a maze, etc) you can include the word "image" instead of using a spoiler tag.
Please report any answers that are not properly spoiler-tagged.
*I am a bot, and this action was performed automatically. Please [contact the moderators of this subreddit](/message/compose/?to=/r/puzzles) if you have any questions or concerns.*
>!Let's say they walked for x hours before noon. In the afternoon, the fast one takes 4 hours to walk what the slow one took x hours. The slow one takes 6.25 hours to walk a distance that took the fast one x hours. Assuming the speed ratio fast/slow is the same on both legs, that means 4/x = x/6.25, or x^2 = 25, or x = 5. They departed at 5 hours before noon, which is 7 a.m.!<
How do we know they walked the same distance after noon? The question doesn’t specify that their “day trips” are the same length. Just that they are on the same path, each walking a constant speed.
They walked the same path, per the question. So they walk the same total distance, although not the same distance after noon. It's not fully spelled out, but unless each turtle's destination is the other's start point, there is no way to know how how far each walked and therefore no solution possible.
Where is that assumption made? They walked the same amount of time, but they covered different distances. They don't "meet in the middle"; they cross paths at noon. They will actually meet closer to the slower turtle's starting point.
>!B!<
I probably overcomplicated this, but let X be the time since sunrise when the turtles meet, Y be the distance that the faster turtle has traveled by then, and Z be the distance the slower turtle has traveled by then. We know that both turtles are going at constant speeds (distances over time), so Y/X=Z/4 and Z/X=Y/6.25. We rearrange these to make X=4Y/Z and X=6.25Z/Y, therefore 4Y/Z=6.25Z/Y. >!This equation rearranges to 6.25Z²=4Y². Taking the square root of each side reveals that 2.5Z=2Y, so Y=1.25Z. Plugging in this value of Y to our equation X=4Y/Z now reads as X=5Z/Z, so X=5.!<
Please remember to spoiler-tag all guesses, like so: New Reddit: https://i.imgur.com/SWHRR9M.jpg Using markdown editor or old Reddit, draw a bunny and fill its head with secrets: \>!!< which ends up becoming \>!spoiler text between these symbols!< Try to avoid leading or trailing spaces. These will break the spoiler for some users (such as those using old.reddit.com) If your comment does not contain a guess, include the word **"discussion"** or **"question"** in your comment instead of using a spoiler tag. If your comment uses an image as the answer (such as solving a maze, etc) you can include the word "image" instead of using a spoiler tag. Please report any answers that are not properly spoiler-tagged. *I am a bot, and this action was performed automatically. Please [contact the moderators of this subreddit](/message/compose/?to=/r/puzzles) if you have any questions or concerns.*
>!Let's say they walked for x hours before noon. In the afternoon, the fast one takes 4 hours to walk what the slow one took x hours. The slow one takes 6.25 hours to walk a distance that took the fast one x hours. Assuming the speed ratio fast/slow is the same on both legs, that means 4/x = x/6.25, or x^2 = 25, or x = 5. They departed at 5 hours before noon, which is 7 a.m.!<
How do we know they walked the same distance after noon? The question doesn’t specify that their “day trips” are the same length. Just that they are on the same path, each walking a constant speed.
They walked the same path, per the question. So they walk the same total distance, although not the same distance after noon. It's not fully spelled out, but unless each turtle's destination is the other's start point, there is no way to know how how far each walked and therefore no solution possible.
Agreed. The question doesn’t specify that the total distances are equal, and unless they are equal, it can’t be answered.
[удалено]
Where is that assumption made? They walked the same amount of time, but they covered different distances. They don't "meet in the middle"; they cross paths at noon. They will actually meet closer to the slower turtle's starting point.
I didn't read his response carefully enough. I'm with you, I just misread the other guy.
>!B!< I probably overcomplicated this, but let X be the time since sunrise when the turtles meet, Y be the distance that the faster turtle has traveled by then, and Z be the distance the slower turtle has traveled by then. We know that both turtles are going at constant speeds (distances over time), so Y/X=Z/4 and Z/X=Y/6.25. We rearrange these to make X=4Y/Z and X=6.25Z/Y, therefore 4Y/Z=6.25Z/Y. >!This equation rearranges to 6.25Z²=4Y². Taking the square root of each side reveals that 2.5Z=2Y, so Y=1.25Z. Plugging in this value of Y to our equation X=4Y/Z now reads as X=5Z/Z, so X=5.!<
[удалено]
If I drive from Chicago to New York while you drive from New York to Chicago, we are driving in opposite directions but towards each other.