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Three Switches and One Light Bulb
This Medium puzzle in the “logic” category rewards careful reading and step-by-step reasoning. Use the hint if you are stuck, then compare your approach with the explained answer.
You are outside a closed room.
Outside the room are 3 switches, but only one of them controls a light bulb inside the room.
You may turn the switches on and off as much as you like, but you may enter the room only once.
How can you determine which switch controls the bulb?
Preparing…