Question 234331: a boy is twice as old as his brother , 4 year a ago he was 3 times as old as his brother. find thier present ages Answer by checkley77(12844) (Show Source):
You can put this solution on YOUR website! boy=2x age now
brother=x age now
2x-4=3(x-4)
2x-4=3x-12
2x-3x=-12+4
-x=-8
x=8 is the age of the brother now.
boy=2*8=16 the age of the boy now.
Proof:
2*8-4=3(8-4)
16-4=3*4
12=12
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