Four suspects (A, B, C, D) are interviewed about a stolen watch. A says: 'B did it.' B says: 'D did it.' C says: 'I didn't do it.' D says: 'B lied when he said I did it.' If exactly three of these statements are true and one is false, who stole the watch?
B
If B is the thief: A's statement ('B did it') is True; B's statement ('D did it') is False; C's statement ('I didn't') is True; D's statement ('B lied') is True. This produces exactly three true statements and one false statement.
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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