A rare gemstone is stolen from a locked gallery. Security footage shows the thief entered at 8:00 PM and left at 8:15 PM. Four suspects give alibis: Alex was reading a book from 7:30 to 8:30 PM. Blair was jogging outside from 7:45 to 8:10 PM. Chris was asleep from 7:00 to 9:00 PM. Dana was cooking dinner from 8:05 to 8:45 PM. Who could not have committed the theft?
Alex
Alex was continuously reading from 7:30 to 8:30 PM, which covers the exact window of the theft (8:00 to 8:15 PM). The other suspects have gaps in their alibis that overlap with the crime window.
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: Easy. More like this: Logic riddles with answers or try Einstein's Logic Grid for a different kind of puzzle.
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