A lock requires a 3-digit combination. The second digit is twice the first digit, and the third digit is three times the first digit. The sum of all three digits is 12. What is the code?
246
Let the first digit be x. The second digit is 2x and the third digit is 3x. Their sum is x + 2x + 3x = 6x = 12, which gives x = 2. Therefore, the digits are 2, 4, and 6.
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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