A rare manuscript was stolen from a glass case that required a four-digit PIN. The curator noted that the PIN was written on a sticky note attached to the back of the computer monitor. Three staff members knew where it was. Inspector Cruz checked the keypad and noticed two buttons had slightly faded paint, while the other eight buttons were pristine. How many digits were actually in the PIN?
Two digits
Only two buttons showed wear, meaning the PIN used only two unique numbers repeated, rather than four different digits.
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: Hard. More like this: Detective riddles with answers or try Truth & Lie Island for a different kind of puzzle.
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