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Twice as old as you were when I was your age

agesalgebraword-problemclassic

Ann says to Ben: "I am twice as old as you were when I was as old as you are now." Ann is 24.

How old is Ben? Unpick the sentence carefully; it refers to two different moments in time, and the trap is to treat "when I was as old as you are now" as if it were happening today rather than some years ago.

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Let Ben's age now be B. "When I was as old as you are now" was some number of years ago. How many? And how old was Ben then?

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