You're trapped in a room with 3 switches for 10 minutes. There are 3 light bulbs outside the room , but you don't know which switch corresponds to which light bulb. What do you do in the 10 minutes you're in the room to figure out which switch corresponds to which light bulb when you walk out?

Question

You're trapped in a room with 3 switches for 10 minutes.  There are 3 light bulbs outside the room , but you don't know which switch corresponds to which light bulb.  What do you do in the 10 minutes you're in the room to figure out which switch corresponds to which light bulb when you walk out?

Anonymous · Accepted Answer

turn on two switches for 10 minutes and leave one off.  Then, right before you leave turn off another one so that one switch is up and the other 2 are down.  Obviously the on light bulb corresponds to the high switch.  The off but still warm light bulb corresponds to the switch that was just turned off.  The other off bulb corresponds to the other switch

Anonymous · Answer

Or, turn on 1 switch for 10 minutes, just before leaving turn it off and turn on the second switch and exit.
first switch - the bulb that is off but warm.
second - bulb that is on
third - cold and off

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