Question 743426
Father's age is six times his son's age. Nine years hence the age of father will be three times his son's age. Find their present ages. 
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Equations:
f = 6s
f+9 = 3(s+9)
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Substitute for "f" and solve for "s":
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6s+9 = 3s + 27
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3s = 18
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s = 6
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Cheers,
Stan H.
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