Math is the closest thing to magic that actually exists (and we can work on).
My Favorite Math Problem
11–20 of 86 posts
Re: My Favorite Math Problem
#12I came across one of my favorite math problems in high school and it blew my mind. ABC DEF + GHI ----- 123J Each letter represents a distinct digit 0-9. What is J? Of course you can write a short program that iterates through the possibilities. But there is also a very elegant solution that fits in a tweet. (If you don't want to try solving it, or have tried and have given up, here is the solution: https://twitter.co…
Does each letter lie in [0,9] or did you mean [1,9]?
Re: My Favorite Math Problem
#13I came across one of my favorite math problems in high school and it blew my mind. ABC DEF + GHI ----- 123J Each letter represents a distinct digit 0-9. What is J? Of course you can write a short program that iterates through the possibilities. But there is also a very elegant solution that fits in a tweet. (If you don't want to try solving it, or have tried and have given up, here is the solution: https://twitter.co…
Does each letter lie in [0,9] or did you mean [1,9]?
There's 10 letters including J so 0 is allowed
Re: My Favorite Math Problem
#14Re: My Favorite Math Problem
#15I came across one of my favorite math problems in high school and it blew my mind. ABC DEF + GHI ----- 123J Each letter represents a distinct digit 0-9. What is J? Of course you can write a short program that iterates through the possibilities. But there is also a very elegant solution that fits in a tweet. (If you don't want to try solving it, or have tried and have given up, here is the solution: https://twitter.co…
My favorite in this line is send+more=money.
Re: My Favorite Math Problem
#16Bunch of problems like this are in the book "Problem-Solving Strategies" by Arthur Engel [1], I believe even including this particular one. Fun book. [1] https://www.google.com/books/edition/Problem_Solving_Strateg...
Or anything with Martin Gardner's name on it. All worth reading.
Re: My Favorite Math Problem
#17My favorite pet math problem so far is: how many times of day are all three hands on a clock equal parts apart?
I have a close but wrong answer that is more interesting than the right answer. I wish I knew of a STEM periodical that accepted amateur articles because I want to do a write-up on this.
Re: My Favorite Math Problem
#18This problem reminds me of another problem.
There is a round table and two players, A and B. The players take turns placing a coin on the table in any location they desire, but coins may not overlap. The first person who is unable to place a coin loses. What is the winning first move?
Answer: the winning move is for player A to place the first coin in the center of the table. After that, no matter which location player B chooses, player A can always play the 180 degree rotationally symmetric location.
Re: My Favorite Math Problem
#19My favorite pet math problem so far is: how many times of day are all three hands on a clock equal parts apart? I have a close but wrong answer that is more interesting than the right answer. I wish I knew of a STEM periodical that accepted amateur articles because I want to do a write-up on this.
> My favorite pet math problem so far is: how many times of day are all three hands on a clock equal parts apart?
Depends on the clock.
(Three hand clocks can be d/h/m or h/m/s.)
Re: My Favorite Math Problem
#20My favorite pet math problem so far is: how many times of day are all three hands on a clock equal parts apart? I have a close but wrong answer that is more interesting than the right answer. I wish I knew of a STEM periodical that accepted amateur articles because I want to do a write-up on this.
> My favorite pet math problem so far is: how many times of day are all three hands on a clock equal parts apart? Depends on the clock. (Three hand clocks can be d/h/m or h/m/s.)
The differential equations would be the same, just with different coefficients.