3 Switches

You are standing in front of a room with one lightbulb inside of it. You cannot see if it is on or off. Outside the room there are 3 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 lightbulb. How?

With pointed fangs it sits in wait, 6 in roman facebooktwittergoogle_plusredditpinterestlinkedinmail