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Five years ago A was thrice as old as B. Ten years later A will be twice as old as B. Find their present ages.
AA=50, B=20
BA=45, B=18
CA=40, B=15
DA=35, B=10
Answer & Solution
Correct answer: A. A=50, B=20
Let now A = x, B = y. Conditions: x − 5 = 3(y − 5) and x + 10 = 2(y + 10). From the first: x = 3y − 10. Sub in the second: 3y − 10 + 10 = 2y + 20 ⇒ y = 20, x = 50.
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