If you multiply my age three years from now by my age three years ago, the result is 72. How old am I today?
9 years old
Let age be x. (x + 3)(x - 3) = 72 => x^2 - 9 = 72 => x^2 = 81. Since age must be positive, x = 9.
About this riddle
Math riddles hide a calculation inside a short story. Pull out the numbers, work out what is being asked, and watch for a trick such as a unit change.
Difficulty: Medium. More like this: Math riddles with answers or try Target 24 for a different kind of puzzle.
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