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3 Switch for 1 Bulb Brain Teaser Riddle
There is a lightbulb inside a closet. The door is closed, and you cannot see if the light is on or off through the door. However, you know the light is off to start.
Outside of the closet, there are three light switches.
One of the door light switches controls the lightbulb in the closet. You can flip the switches however you want, but once you open the door, you can no longer touch the switches.
How do you figure out without a doubt which of the three light switches controls the light?
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Think about it for a minute, then scroll down...
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Ready for the answer?
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Here it is:
Flip switch number 1 and wait a few minutes. Flip switch number 1 back to its original position, and then immediately flip switch number 2.
Open the door. If the light is on, then switch number 2 controls it. If the light is off, then go and feel the bulb with your hand. If the bulb is hot, then switch number 1 controls it, and if the bulb is cold, then switch number 3, the one you did not touch, controls it.
- Hugo Merminod
