I am a three-digit number. My tens digit is 0. My hundreds digit is 4 times my units digit. If the sum of all my digits is 10, what number am I?
802
Let the number be h0u. h + 0 + u = 10 -> h + u = 10. Also h = 4u. Substitute 4u + u = 10 -> 5u = 10 -> u = 2. Then h = 4(2) = 8. The number is 802.
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: Medium. More like this: Math riddles with answers or try Target 24 for a different kind of puzzle.
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