A priceless vase was reported stolen from an eccentric collector's vault. The vault required a 6-digit PIN known only to the collector. The collector swore he never wrote it down. Detective Fox inspected the numeric keypad and immediately knew the PIN without asking anyone. How?
The keys for the 6 digits showed much more wear and tear (oil, fading) than the unused keys.
Even if a password is kept secret, frequent pressing of the exact same six buttons wears down the matte finish or leaves microscopic skin oils on those specific keys, narrowing the possible combinations down significantly.
About this riddle
Detective riddles are tiny mysteries. Look for the detail in the story that does not fit; it is usually the clue that solves the case.
Difficulty: Easy. More like this: Detective riddles with answers or try Truth & Lie Island for a different kind of puzzle.
More detective riddles
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