Add me to myself, and I remain unchanged. Multiply me by any number in the universe, and only I remain. Which number am I?
0
Zero is the additive identity and the zero-product element: 0 + 0 = 0, and 0 × x = 0 for any number x.
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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