I am a three-digit number. My tens digit is zero. My hundreds digit is three times my units digit. The sum of all my digits is 12. What number am I?
903
Let the number be h0u. We know h + 0 + u = 12, and h = 3u. Substituting gives 3u + u = 12, so 4u = 12, which means u = 3. Then h = 9. The number is 903.
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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