Question 834385
You can say:
Let {{{ c }}} = the child's age at a certain point in time
You know that the parent's age at that time will be {{{ c + 32 }}}
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Now say that point in time is when  
{{{ c = (1/2)*( c + 32 ) }}}
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{{{ 2c = c + 32 }}}
{{{ c = 32 }}}
So when the child is 32, the parent is {{{ c + 32 = 64 }}}
Hope this helps