A padlock requires a 3-digit code using distinct digits from 1 to 9. 1. The sum of the three digits is 15. 2. The second digit is double the first digit. 3. The third digit is an odd number greater than the second digit. What is the 3-digit code?
249
Let digits be A, B, C. B = 2A, so A + 2A + C = 15, meaning 3A + C = 15. If A=1, C=12 (invalid). If A=3, C=6 (not odd). If A=4, B=8, C=3 (not greater than B). Thus A=2, B=4, and C=9, yielding 249.
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: Hard. More like this: Logic riddles with answers or try Einstein's Logic Grid for a different kind of puzzle.
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