Three light switches (Red, Green, Blue) sit outside a closed room. Exactly one switch turns on the desk lamp inside. Flipping the Red switch turns on a wall fan. Flipping the Green switch turns on an overhead ceiling light. Which switch turns on the desk lamp?
Blue switch
Red and Green are already linked to other appliances (fan and ceiling light), leaving the Blue switch as the only one that can operate the desk lamp.
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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