document.write( "Question 766591: Please help me solve this puzzle \"If there are 3 switches outside the room corresponding to 3 bulbs inside the room, how will you know which switch belong to which bulb. Only once you can enter in room.\" \n" ); document.write( "

Algebra.Com's Answer #467124 by Edwin McCravy(20056) $\"\"$ $\"About$

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Please help me solve this puzzle \"If there are 3 switches outside the room corresponding to 3 bulbs inside the room, how will you know which switch belong to which bulb. Only once you can enter in room.\"
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document.write( "1. You turn switches 1 and 2 on.\r\n" );
document.write( "2. Wait a few minutes.\r\n" );
document.write( "3. You turn switch 1 off, leaving switch 2 on.\r\n" );
document.write( "4. You open the door.\r\n" );
document.write( "5. You will find:\r\n" );
document.write( "   One bulb is on. That bulb is controlled by switch 2, the only\r\n" );
document.write( "   switch that is on.\r\n" );
document.write( "6. You feel the bulbs that are off. One is warm and the other is cold.\r\n" );
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document.write( "The bulb that is off and warm is controlled by switch 1, for switch\r\n" );
document.write( "1 was on long enough to warm up the bulb it controls.\r\n" );
document.write( "The light that is off and cold is controlled by switch 3, for switch 3\r\n" );
document.write( "has not been turned on at all.\r\n" );
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document.write( "Edwin

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