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Age of kids

  1. Apr 2, 2007 #1
    I have applied my supreme translation skills but it still can be somewhat bad english. Any way, here it goes.

    So, there were 2 men sitting in a park.
    - So, got any kids?
    - Two sons.
    - Which school are they in?
    - They aren't going there yet.
    - So, how old are they?
    - Their ages product is equal to numbers of pigeons over there.
    - That's not enough.
    - Oh... youngest looks more like his mom.
    - Ooookay, I've got it.

    Additional info: in Russia, children go to school at 7.
     
  2. jcsd
  3. Apr 2, 2007 #2
    Answer is hidden:

    If there were no pigeons, the conversation would have gone differently so both kids are at least 1 year old.
    The only ambiguous products of the numbers from 1 to 6 are 4, 6, and 12:
    4 = 1 x 4 and 2 x 2
    6 = 1 x 6 and 2 x 3
    12 = 2 x 6 and 3 x 4
    Of these, the only one that is disambiguated by knowing that the two ages are not equal is 4. The kids are 1 and 4 years old.

    eom
     
  4. Apr 3, 2007 #3
    ...though it's not so hidden in email :grumpy:
     
  5. Apr 3, 2007 #4
    I don't understand, I didn't send an e-mail. Anyone can 'unhide' the text by dragging the cursor over it.
     
  6. Apr 3, 2007 #5
    if someone subscribes to this (any) thread, and then another person posts "hidden" answer, an email is sent to 1st person with message copy, where answer is no longer hidden, and so 1st person has no option to ignore it. not that it's much of a problem, but I thought I'd point it out.
     
  7. Apr 3, 2007 #6
    I see. This is a weakness in the mail transcription process. The point of the hidden text is so that anyone who doesn't want to be told the answer can more easily avoid reading it. If such a person subscribes, then they should use the e-mail as a kind of wake-up call, but should not read the contents of the message. In the case when the poser of the brain-teaser has subscribed, I expect no desire to avoid reading the proposed solutions.
     
    Last edited: Apr 3, 2007
  8. Jun 6, 2007 #7
    The most important thing in this problem: a Russian did get the solution. I can see only possibilities but not an answer.



    ___________________________
    online casino
     
  9. Aug 29, 2007 #8
    There must be more than 1 pigeon, but less than 49.

    This leaves several possible solutions for the product of ages:

    1 x 2
    3 x 1
    4 x 1
    5 x 1
    6 x 1

    2 x 2
    2 x 3
    2 x 4
    2 x 5
    2 x 6

    3 x 3
    3 x 4
    3 x 5
    3 x 6

    4 x 4
    4 x 5
    4 x 6

    5 x 5
    5 x 6

    6 x 6


    Assuming the 2 boys are not the same age, gives these solutions:

    1 x 2
    3 x 1
    4 x 1
    5 x 1
    6 x 1

    2 x 3
    2 x 4
    2 x 5
    2 x 6

    3 x 4
    3 x 5
    3 x 6

    4 x 5
    4 x 6

    5 x 6


    There is NO solution. (But from this, I can say the maximum number of pigeons is 30).
     
    Last edited: Aug 29, 2007
  10. Aug 29, 2007 #9
    Scarecrow, this bit of information "- Oh... youngest looks more like his mom.
    - Ooookay, I've got it." let's you know you are looking for a perfect square that only has two factors aside from its root.
     
  11. Aug 29, 2007 #10
    What makes you think you can extract that information from that line? Just wondering.
     
  12. Aug 29, 2007 #11
    The man asking the questions was obviously hesitating between two possibilities: either the kids have the same age, or one is older than the other. As soon as he learns that there's a difference, he is able to know which possibility is the right one. The number of pigeon is hence a perfect square; had it not been so, the revelation of an age difference wouldn't be of any use. This said, the perfect square we are looking for only has two other factors aside from its root: or else the revelation of an age difference wouldn't be enough information.
     
  13. Aug 29, 2007 #12
  14. Oct 14, 2007 #13
    Maybe the boys are 1 and 4 years old
     
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