Add me to myself and multiply by 4. Then divide by 8 and you will get back to me. What number am I?
Any number
Let the number be x. (x + x) * 4 / 8 = 2x * 4 / 8 = 8x / 8 = x. This works for any real number.
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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