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  1. #1
    4 Star Lounger
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    Interesting Ancestry

    Last week, Alf managed to trace his family tree back as far as 500 AD. In so doing, he noticed a few interesting facts and so he decided to tease his friend with a puzzle. He had discovered that:

    Ancestor x was x years old in the year x squared.

    His son was y years old in the year y cubed.

    Rob was unable to provide a solution for x and y given that information.

    Alf then revealed that Ancestor x was Rob's age when y was born.

    How old was Ancestor x when his son was born?

    Rob, as usual, still could not provide the answer. Can you?
    <font color=blue><font face="Script MT Bold"><big>Rob</big></font face=script></font color=blue>

  2. #2
    Plutonium Lounger
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    Re: Interesting Ancestry

    <span style="background-color: #FFFF00; color: #000000; font-weight: bold"><font color=yellow>This is a bit ambigouous. If Rob could still not provide the answer to the original question ("provide a solution for x and y"), the answer to the second question is 60:

    x = 31, y = 10 leads to: x was born in 31^2 - 31 = 930, and y in 10^3 - 10 = 990, so x was 60 when y was born.
    x = 36, y = 11 leads to: x was born in 36^2 - 36 = 1260, and y in 11^3 - 11 = 1320, so x was also 60 when y was born.
    Rob is also 60 years old, so he can't determine x and y.

    If Rob could not provide the answer to the second question ("how old was ancestor x when his son was born?"), I don't know the answer either.</font color=yellow></span hi>

  3. #3
    4 Star Lounger
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    Re: Interesting Ancestry

    Spot on, Hans!
    <font color=blue><font face="Script MT Bold"><big>Rob</big></font face=script></font color=blue>

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