Question 1162985
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Mum + Dad   + Joel       = 99,   or


  x + (x-4) + ((x-4)-37) = 99.


Simplify and solve


  3x - 45 = 99

  3x      = 99 + 45

   x      = 33 + 15 = 48.     Mum's age.     <U>ANSWER</U>
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