Question 1103206
 Travis is 24 years older than his sister Danielle. 
In 13 years, he will be twice as old as Danielle.
How old is each of them now?
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T = D + 24
T+13 = 2(D+13)
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Substitute for "T" and solve for "D"::
D+24 + 13 = 2D + 26
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D = 11 (Danielle's age now)
T = D+24 = 35 (Travis' age now)
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Cheers,
Stan H.
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