I am a positive integer. If you cube me and then subtract me from the result, the answer is always a multiple of what number?
6
By number theory, n^3 - n factors into (n-1)n(n+1), which is the product of three consecutive integers. The product of three consecutive integers is always divisible by 6.
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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