A father is currently four times as old as his daughter. In 20 years, he will be exactly twice as old as she is then. How old is the father right now?
40 years old
Let D be the daughter's current age. The father is 4D. In 20 years, 4D + 20 = 2(D + 20). Simplifying gives 4D + 20 = 2D + 40, so 2D = 20 and D = 10. The father is currently 4 * 10 = 40 years old.
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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