A code of four distinct digits is required to open a vault. The first digit is double the last digit. The second digit is the sum of the first and last digits. The third digit is half of the second digit. If the last digit is 2, what is the complete 4-digit code?
4632
Let's find each digit step by step. Last digit = 2. First digit is double the last (2 * 2 = 4). Second digit is the sum of first and last (4 + 2 = 6). Third digit is half of the second (6 / 2 = 3). Putting them in order: 4, 6, 3, 2.
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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