A detective interviews three suspects: Amy, Bob, and Charlie. Exactly one suspect is guilty. Amy says, 'I am innocent.' Bob says, 'Amy is guilty.' Charlie says, 'Amy is innocent.' If exactly ONE of these three statements is true, who is the guilty suspect?
Amy
If Amy is guilty: Amy's statement is False, Bob's statement is True, and Charlie's statement is False. This yields exactly 1 true statement. If Bob or Charlie were guilty: both Amy and Charlie would be telling the truth, yielding 2 true statements. Thus, Amy must be the guilty suspect.
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.
More logic riddles
A row goes: clover, clover, gold coin, clover, clover, gold coin, clover, clover. What comes next?
I am a five-digit number. My first digit is half of my second. My third digit is the sum of the first two. My fourth digit is equal to my second digit minus one. My fifth digit is triple my first digit. If all my digits are unique, what number am I?
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?
A thief steals a watch from a store. A detective deduces that the thief must have entered through the window because the front door was locked from the inside, no keys were missing, and footprints on the windowsill match the stolen item's dust residue. However, the store is on the 10th floor of a building with no exterior ladders or scaffolding. How did the thief escape?
A painter is standing on the middle rung of a wooden ladder leaning against a wall. She climbs up 3 rungs, drops her brush and descends 5 rungs, then climbs back up 8 rungs to finish the job. Which rung is she on now relative to her starting position?
What English word becomes shorter when you add two letters to it?