Question 763947: Doug is 19 years older than his sister Barbara. In 3 years, he will be twice as old as Barbara. How old is each of them now? Answer by stanbon(75887) (Show Source):
You can put this solution on YOUR website! Doug is 19 years older than his sister Barbara. In 3 years, he will be twice as old as Barbara. How old is each of them now?
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Equations:
d = b + 19
d+3 = 2(b+3)
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Substitute for "d" and solve for "b":
b+19+3 = 2b+6
b = 16 years (Barbara's age)
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d = b + 19
d = 35 years (Doug's age)
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Cheers,
Stan H.
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