Three detectives—Holmes, Poirot, and Marple—each solve a different mystery involving a missing gem: a Ruby, a Diamond, or an Emerald. 1. Holmes did not solve the mystery of the Ruby. 2. The investigator who solved the Emerald mystery was not Marple. 3. Poirot solved the mystery of the Diamond. Who solved the mystery of the Ruby?
Marple
Poirot solved the Diamond. This leaves the Ruby and Emerald for Holmes and Marple. Since Marple did not solve the Emerald mystery, Marple must have solved the Ruby mystery (and Holmes solved the Emerald mystery).
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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