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Homework Help: Half my age again?

  1. Mar 22, 2012 #1
    1. The problem statement, all variables and given/known data
    I need a rock solid proof.

    Is it possible to be half someones age more than once?

    Eg. I was born at 0 while my dad was born at 20, he will be 40 when I am 20 hence I am half his age. Is this possible more than once?
  2. jcsd
  3. Mar 22, 2012 #2
    The difference in your ages is fixed. Use that constant to show that the fraction only ever decreases.

    (Quibble: in your example, if I die when I'm 30, will I again be half my Dad's age when he turns 60?)
  4. Mar 22, 2012 #3
    You have two ages, which can be represented by functions which are linear in time, what do you know about the solutions to systems of linear equations?
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