I am a three-digit number. My tens digit is twice my hundreds digit, and my ones digit is three times my hundreds digit. If the sum of all my digits is 12, what number am I?
246
Let hundreds digit be H. Tens = 2H. Ones = 3H. Sum = H + 2H + 3H = 6H = 12, so H = 2. Hundreds = 2, Tens = 2(2) = 4, Ones = 3(2) = 6. The number is 246.
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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