If you multiply me by myself, add 5, and then divide by 3, you get 10. What number am I?
5
Working backwards: 10 times 3 is 30. Subtract 5 to get 25. The square root of 25 is 5 (or -5, but 5 is standard for these riddles).
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: Easy. More like this: Math riddles with answers or try Target 24 for a different kind of puzzle.
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