A father is four times as old as his son. In 20 years, the father will be only twice as old as his son. How old is the son right now?
10
Let son be X, father be 4X. In 20 years: 4X + 20 = 2(X + 20). 4X + 20 = 2X + 40, so 2X = 20, making X = 10.
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: Hard. More like this: Math riddles with answers or try Target 24 for a different kind of puzzle.
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