A password consists of four distinct single-digit numbers. The first digit is three times the third digit. The second digit is two more than the fourth digit. The sum of all four digits is 16. What is the password?
6523
Let the digits be A, B, C, D. A = 3C. B = D + 2. A + B + C + D = 16. Try C = 2 -> A = 6. Remaining sum for B + D = 16 - 6 - 2 = 8. We know B = D + 2, so (D + 2) + D = 8 -> 2D = 6 -> D = 3. Thus B = 5. The digits are 6, 5, 2, 3.
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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