I am a two-digit whole number. My tens digit is double my units digit. If you add my digits together, you get 12. What number am I?
84
Let U be the units digit and T be the tens digit. T = 2U and T + U = 12. Substituting T gives 2U + U = 12, so 3U = 12, meaning U = 4 and T = 8.
About this riddle
Logic riddles give you a few facts and ask what must be true. List what you know, cross out what cannot be, and see what is left.
Difficulty: Easy. More like this: Logic riddles with answers or try Einstein's Logic Grid for a different kind of puzzle.
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