SOLUTION: A boy now one third as old as his father ,twelve years later he will be half as old as his father.then the present age of the boy is

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Question 995160: A boy now one third as old as his father ,twelve years later he will be half as old as his father.then the present age of the boy is
Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
A boy now one third as old as his father ,twelve years later he will be half as old as his father.then the present age of the boy is
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Equations:
b = (1/3)f
b+12 = (1/2)(f+12)
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Substitute for "b" and solve for "f"::
(1/3)f + 12 = (1/2)(f+12)
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Multiply thru by 6 to get rid of the fractions::
2f + 72 = 3(f+12)
2f + 72 = 3f + 36
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f = 36 (father's age now)
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boy = (1/3)f = 12 yrs
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Cheers,
Stan H.
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