I am an odd three-digit number. All of my digits are different. My tens digit is the sum of my hundreds and units digits. My hundreds digit is 1. What number am I?
123
Hundreds digit is 1. Tens digit equals hundreds (1) plus units. Since units must be a distinct digit and the number is odd, units can be 3, 5, 7, or 9. If units is 3, tens is 1 + 3 = 4? Wait, tens is sum of hundreds and units: 1 + 3 = 4, making the number 143. Let's check: 143 is odd, digits are different, tens (4) = 1 + 3. Let's check if 123 works: hundreds=1, units=3, tens=2. Does tens = 1+3? No, 2 != 4. So 143 is correct. Let's adjust the question to fit 143.
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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