I am a two-digit number. My tens digit is three times my units digit. If you reverse my digits, the new number is 36 less than my original value. What number am I?
62
Let the tens digit be T and units digit be U. T = 3U. The original number value is 10T + U and the reversed number is 10U + T. Their difference is (10T + U) - (10U + T) = 9(T - U) = 36, which means T - U = 4. Substituting T = 3U into this equation gives 3U - U = 4, so 2U = 4 and U = 2. Therefore T = 6, making the original number 62.
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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