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Brain teaser
#1
Brain teaser
You are outside of a room with no windows and just one door. On the wall next to the door are three light switches. The only thing in the room is a single light bulb hanging from a flex.

Your job is to determine which light switch operates the bulb inside the room.

All the time the door is shut you can play around with the switches as much as you like.

But, once you open the door you cannot touch the switches again and you must make your decision.

The room is completely sealed and you cannot see inside without opening the door.

How do you work out which switch operates the light?
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Messages In This Thread
Brain teaser - by Darwinian - August 27, 2008 at 1:37 pm
RE: Brain teaser - by Tiberius - August 27, 2008 at 2:38 pm
RE: Brain teaser - by LondonLoves - August 27, 2008 at 3:26 pm
RE: Brain teaser - by Tiberius - August 27, 2008 at 3:28 pm
RE: Brain teaser - by Brick-top - August 27, 2008 at 5:11 pm
RE: Brain teaser - by StewartP - August 27, 2008 at 5:26 pm
RE: Brain teaser - by Brick-top - August 27, 2008 at 5:33 pm
RE: Brain teaser - by Darwinian - January 8, 2009 at 2:06 pm
RE: Brain teaser - by Tiberius - August 27, 2008 at 6:12 pm
RE: Brain teaser - by Darwinian - August 27, 2008 at 7:17 pm
RE: Brain teaser - by Brick-top - August 27, 2008 at 7:11 pm
RE: Brain teaser - by Darwinian - August 27, 2008 at 7:20 pm
RE: Brain teaser - by Tiberius - August 27, 2008 at 7:28 pm
RE: Brain teaser - by Tiberius - August 27, 2008 at 7:33 pm
RE: Brain teaser - by StewartP - August 28, 2008 at 5:30 am
RE: Brain teaser - by Darwinian - January 8, 2009 at 12:11 pm
RE: Brain teaser - by CoxRox - January 8, 2009 at 1:38 pm
RE: Brain teaser - by Tiberius - January 9, 2009 at 5:27 pm
RE: Brain teaser - by Darwinian - January 12, 2009 at 5:15 pm
RE: Brain teaser - by CoxRox - January 12, 2009 at 5:11 pm
RE: Brain teaser - by Darwinian - January 13, 2009 at 1:58 pm
RE: Brain teaser - by CoxRox - January 13, 2009 at 5:30 pm
RE: Brain teaser - by Darwinian - January 13, 2009 at 5:56 pm
RE: Brain teaser - by CoxRox - January 15, 2009 at 5:08 pm
RE: Brain teaser - by Darwinian - January 16, 2009 at 12:10 am
RE: Brain teaser - by CoxRox - January 14, 2009 at 10:03 am
RE: Brain teaser - by Darwinian - January 14, 2009 at 10:12 am
RE: Brain teaser - by Tiberius - January 14, 2009 at 1:44 pm
RE: Brain teaser - by Sam - January 14, 2009 at 4:21 pm
RE: Brain teaser - by downbeatplumb - January 14, 2009 at 4:54 pm
RE: Brain teaser - by Rob - January 14, 2009 at 8:40 pm
RE: Brain teaser - by Sam - January 15, 2009 at 12:44 pm
RE: Brain teaser - by Rob - January 15, 2009 at 3:49 pm
RE: Brain teaser - by Darwinian - January 15, 2009 at 4:54 pm
RE: Brain teaser - by Darwinian - January 16, 2009 at 12:36 am
RE: Brain teaser - by Tiberius - January 16, 2009 at 3:20 am
RE: Brain teaser - by Darwinian - January 16, 2009 at 3:30 am

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