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Homework Help: Equation from a riddle

  1. Mar 7, 2010 #1
    hi all ,,,,

    1. The problem statement, all variables and given/known data

    Four years ago, kelly was twice as old as her brother. Find the present age of kelly and
    her brother if the product of their ages today is 160.



    3. The attempt at a solution

    well,, I tried with this method

    2x+x=152 ,,,,, => ( 2x+4 ) + (x+4) = 160 ,,,, the answer I got was 152/3


    my teacher told me , my answer is wrong


    can anyone help me with making an equation ,,,,
     
  2. jcsd
  3. Mar 7, 2010 #2

    Borek

    User Avatar

    Staff: Mentor

    Try with two variables, say K for Kelly and B for Brother.

    Try to write equation for

     
  4. Mar 7, 2010 #3
    thx a lot my brother ,,,, i didn't focus on product ,,,
     
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