A vault requires a four-digit numerical code. The first digit is double the last digit. The second digit is three less than the first digit. The third digit is the sum of the first and second digits. If the last digit is 2, what is the code?
4152
Last digit = 2. First digit is double the last (2 * 2 = 4). Second digit is three less than the first (4 - 3 = 1). Third digit is the sum of the first and second (4 + 1 = 5). Putting them in order gives 4, 1, 5, 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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