# You are standing in front of a room with one light bulb inside of it. You can not see if it is on or off................

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You are standing in front of a room with one light bulb inside of it.
You can not see if it is on or off.
Outside the room there are three switches in the off positions.
You may turn the switches any way you want to.
You stop turning the switches, enter the room and know which switch controls the light bulb. how?

posted Aug 22, 2018

Switch 1- leave off
Switch 2- turn on and leave for a minute or so to warm up the bulb, turn off
Switch 3- turn on and enter the room
If light is on- it's linked to switch 3, if light is off and bulb is warm- it's linked to switch 2, if light is off and bulb is cold- it's linked to switch 1.

the switches were already turned off so it was easy to know how to turn it on.

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