If you multiply me by 3, subtract 7, and then square the result, you get 100. What positive number could I be?
5 or -1/3 (or 5)
The square root of 100 is 10 or -10. If 3x - 7 = 10, then 3x = 17 (not whole). If 3x - 7 = -10, then 3x = -3, so x = -1. Wait, let's re-eval: if x=5: 5*3=15; 15-7=8; 8^2=64. That's not 100. Let's fix the question/answer. Let's make it: 'If you multiply me by 4, add 4, and divide by 2, you get 16. What number am I?' -> 4x + 4 = 32 -> 4x = 28 -> x=7. Let's use that for a clean riddle instead.
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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