SOLUTION: Dingdong is 15 years older than Marian. Then years ago, he was twice as old as MArian. Find their age.

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Question 708763: Dingdong is 15 years older than Marian. Then years ago, he was twice as old as MArian. Find their age.
Answer by stanbon(75887) About Me  (Show Source):
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Dingdong is 15 years older than Marian. Ten years ago, he was twice as old as MArian. Find their ages.
Equations:
d = m + 15
d-10 = 2(m-10)
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Substitute for "d" and solve for "m":
m+15 - 10 = 2m-20
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m + 5 = 2m-20
m = 25 (Marian's age now)
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Solve for "d":
d = m+15
d = 25+15
d = 40 (Dingdong's age now)_
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Cheers,
Stan H.
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