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        riddles >> easy >> Re: Light Bulbs & Switches Variation
        
(Message started by: rmsgrey on Aug 5^th, 2013, 7:29am)

Title: Re: Light Bulbs & Switches Variation
Post by rmsgrey on Aug 5^th, 2013, 7:29am

on 08/03/13 at 01:38:26, alien2 wrote:

Instead of three, there are four light switches and four light bulbs.

If you're varying the riddle I think you are, then the setup is:

You have 4 switches, with clearly labelled "on" and "off" states, in one room, connected, one each, to 4 bulbs in a nearby room. You are allowed to spend as much time as you wish in the room with the switches, and may flip the switches freely, but may visit the room with the bulbs only once. You are required to identify which switch controls which bulb.

The solution to that puzzle is straightforward:

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Start by flipping switches A and B on, and C and D off.
Wait an hour so bulbs A and B will be on and hot, and C and D will be off and cold.
Flip switches B and C, so:
Bulb A is on and hot
Bulb B is off and hot
Bulb C is on and cold
Bulb D is off and cold
Enter the bulb room and feel all four bulbs to discover which are hot and which are cold. Try not to burn yourself.
[/hideb]