I am a number between 50 and 100. My tens digit is two more than my units digit, and the sum of my digits is 12. What number am I?
75
Let tens be t and units be u. t = u + 2 and t + u = 12. Substitute: (u + 2) + u = 12 -> 2u = 10 -> u = 5. Then t = 5 + 2 = 7. The number is 75, which is between 50 and 100.
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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