I am a positive integer. If you square me, then cube that result, and then take the square root, you get 64. What number am I?
8
Let the number be x. Squaring gives x^2. Cubing that gives (x^2)^3 = x^6. The square root of x^6 is x^3. Since x^3 = 64, x must be 4? Wait. 4^3 = 64. Let's check: 4 squared = 16. 16 cubed = 4096. Square root of 4096 is 64. So the number is 4.
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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