I am a two-digit number. My tens digit is 3 greater than my units digit. If you sum my digits, you get 11. What number am I?
74
Let the units digit be u and tens digit be u + 3. Their sum is u + (u + 3) = 11, so 2u = 8 and u = 4. The tens digit is 4 + 3 = 7, making the number 74.
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: Medium. More like this: Logic riddles with answers or try Einstein's Logic Grid for a different kind of puzzle.
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