You have three distinct keys: Brass, Silver, and Gold. Each opens one of three locked doors: Red, Green, or Blue. The Brass key does not open the Red or Green door. The Silver key does not open the Green door. Which door does the Gold key open?
The Green door
Since the Brass key opens neither Red nor Green, it opens Blue. That leaves Red and Green for Silver and Gold. Silver cannot open Green, so Silver opens Red. Consequently, Gold opens Green.
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: Medium. More like this: Logic riddles with answers or try Einstein's Logic Grid for a different kind of puzzle.
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