A mother is currently three times as old as her daughter. In twelve years, the mother will be exactly twice as old as her daughter. How old is the daughter right now?
12
Let d be the daughter's age and m be the mother's age. We know m = 3d. In 12 years: m + 12 = 2(d + 12). Substituting m gives 3d + 12 = 2d + 24, which simplifies to d = 12.
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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