Four suspects—Amber, Blake, Cody, and Dana—are questioned about a missing ring. Exactly one of them stole it. Amber says: 'Cody took the ring.' Blake says: 'I did not take the ring.' Cody says: 'Dana took the ring.' Dana says: 'Cody is lying.' If exactly one of these four statements is true, who stole the ring?
Blake.
If Blake stole the ring: Amber lies (False), Blake lies about his innocence (False), Cody lies (False), and Dana tells the truth that Cody lied (True). This produces exactly one true statement. Testing any other suspect yields two true statements.
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 courier must deliver four distinct parcels (A, B, C, and D) across a grid, but strict routing protocols apply. Parcel A must be delivered before B. Parcel C cannot be delivered until D has reached its destination. If B is delivered before C, what is the absolute last parcel that can possibly be delivered?
A detective establishes two facts: 1. If the butler lies, then the maid is innocent. 2. If the maid is innocent, then the chef is guilty. The chef is later proven innocent. Is the butler telling the truth or lying?
A row goes: firework, firework, sparkler, firework, firework, sparkler, firework, firework. What comes next?
I am older than my sister, but younger than my brother. My sister is twice as old as my dog, who was born 4 years ago. If my brother is 12, what are my possible whole-number ages?
A row goes: squirrel, squirrel, scarecrow, squirrel, squirrel, scarecrow, squirrel, squirrel. What comes next?
The day before yesterday, Maya was 17 years old. Next year, she will turn 20. How is this logically possible?