I am a three-digit number. My tens digit is three times my units digit, and my hundreds digit is two less than my tens digit. The sum of all my digits is 12. What number am I?
462
Let the digits be H (hundreds), T (tens), and U (units). We are given: T = 3U, H = T - 2, and H + T + U = 12. Substitute T and H in terms of U: (3U - 2) + 3U + U = 12. Combine terms: 7U - 2 = 12, so 7U = 14, which means U = 2. Now find T: T = 3 * 2 = 6. Now find H: H = 6 - 2 = 4. The number is 462.
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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