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How Old Are the Three Sons?

  1. Oct 31, 2004 #1
    I thought this was a good one. All my friends who I've shown it to (except for one) haven't been able to solve it.

    Many years from now, two men are sitting in the county park. The
    following is part of their discussion:

    Man 1: Yes, I'm married and have three fine sons.
    Man 2: That's wonderful! How old are they?
    MaN 1: Well, The product of their ages is equal to 36.
    Man 2: Hmm. That doesn't tell me enough. Give me another clue.
    Man 1: Ok, the sum of their ages is the number on that building
    across the street.
    Man 2: A ha! I've almost got the answer, but I still need another
    Man 1: Very well. The oldest one has red hair.
    Man 2: I've got it!
  2. jcsd
  3. Nov 1, 2004 #2
    in white:
    2 2 9
  4. Nov 2, 2004 #3
    a nice puzzle

    answer in white font 2, 2, and 9 ... there are 6 possible age combinations, only two give ambiguous sums of ages (2, 2, and 9; 1, 6, and 6) and it must be one of these or else the house number would have solved the problem in step 2; only 2, 2, and 9 gives a single 'oldest' child as the alternative (1, 6 and 6 has tiwn boys as oldest
  5. Nov 13, 2004 #4
    Or simply 2, 3 and 6 years old.
  6. Nov 13, 2004 #5
    I make it 9, 2 and 2
  7. Nov 13, 2004 #6


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    At first, that last clue seemed like something of a red hairing. :redface:
  8. Nov 14, 2004 #7


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    Gold Member

    What other integer triplet with product 36 has sum 11 and also has the two largest members being equal to each other ?

    Ha ha...a red hairing, indeed !! :rofl:
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