Proposal: Puzzling

Would Math puzzles - distinguished from Math homework problems, which can usually go on Math Stack Exchange - be on topic here? Example:

Two perfect logicians, S and P, are told that integers x and y have been chosen such that 1 < x < y and x+y < 100. S is given the value x+y and P is given the value xy. They then have the following conversation.

  • P: I cannot determine the two numbers.
  • S: I knew that.
  • P: Now I can determine them.
  • S: So can I.

Given that the above statements are true, what are the two numbers? (Computer assistance allowed.)


  • FYI, this is problem 4 of Round 1 of USA Mathematical Talent Search several years ago. Commented May 8, 2014 at 8:28
  • @PaulDraper You realize that my link is dated 2002 and yours is dated 2005, right?
    – durron597
    Commented May 8, 2014 at 18:49
  • Sure; I suppose I was just showing where it had been used somewhere else than Nick's mathematical puzzles 1 to 10. Commented May 8, 2014 at 20:01

1 Answer 1


I would say this is clearly on topic. Many of these are very interesting. Many are old hat, as well. We will have a lot of duplicates. Making meta links out of the old rec.puzzles FAQ list would be a good idea so we can find them.

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