An ancient vault requires a numerical code. Clue 1: The tens digit is twice the units digit. Clue 2: The sum of all three digits is 12. Clue 3: The hundreds digit is equal to the units digit. What is the 3-digit code?
424
Let units = x. Hundreds = x (Clue 3). Tens = 2x (Clue 1). Sum = x + 2x + x = 4x = 12 (Clue 2). So x = 3? Wait, 4x = 12 means x = 3. Then units = 3, hundreds = 3, tens = 6. Code 363. Let's check: tens (6) is 2x3. Sum = 3+6+3 = 12. Correct answer is 363.
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: Medium. More like this: Logic riddles with answers or try Einstein's Logic Grid for a different kind of puzzle.
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