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Bulbs


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257 replies to this topic

#61 miriramirez

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Posted 27 July 2007 - 09:03 PM

If we assume there is a doorway through which you can visually see the lights turn on and off, you can turn a switch on and then enter the room. You see which light is on and then remove an unlit bulb walk out, turn off the first switch and then turn on another switch. If the room lights up then you turned on the switch with the bulb still attached. If it doesn't you identified it as the one where the bulb was removed. No burnt fingers.
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#62 zlev

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Posted 28 July 2007 - 09:51 PM

There is no restriction that says you cannot seek the help of a friend or even any other human nearby. Thus you simply have someone stand in one room and note which switch they flick (maybe left to right or something) while in the bulb room you note which bulbs light up (or vice versa).
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#63 mdsl

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Posted 30 July 2007 - 12:22 PM

Bulbs - Back to the Logic Puzzles
This is one of my favorite logic puzzles (Edit: it is more a practical than a logic puzzle).
Imagine you are in a room with 3 switches. In an adjacent room there are 3 bulbs (Edit: let's say in lamps which are on a regular table) - all are off at the moment, each switch belongs to one bulb. It is impossible to see from one room to another. How can you find out which switch belongs to which bulb, if you may enter the room with the bulbs only once?

Edit: No help from anybody else is allowed.


There is no restriction that says you cannot seek the help of a friend or even any other human nearby. Thus you simply have someone stand in one room and note which switch they flick (maybe left to right or something) while in the bulb room you note which bulbs light up (or vice versa).



Yeah there is a restriction since this would make the situation a chore not a puzzle.
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#64 ysmile

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Posted 31 July 2007 - 08:19 PM

Bulbs
This is one of my favorite logic puzzles.
Imagine you are in a room with 3 switches. In an adjacent room there are 3 bulbs (all are off at the moment), each switch belongs to one bulb. It is impossible to see from one room to another. How can you find out which switch belongs to which bulb, if you may enter the room with the bulbs only once?



My solutionm to this come from reading the language very carefully. ...In an adjacent room there are 3 bulbs (all are off at the moment)

suggesting that the bulbs are not in their socket...

So i would flick ON only two of the three switches and walk into the other room where the bulbs are and insert two bulbs into their socket (may have to try several sockets). Once those two are lighted...i will know that the switch in the other room that was LEFT on OFF is for the 3rd bulb that is not lighted in the remainig socket..

Megs
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#65 mdsl

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Posted 01 August 2007 - 12:40 PM

Bulbs
This is one of my favorite logic puzzles.
Imagine you are in a room with 3 switches. In an adjacent room there are 3 bulbs (all are off at the moment), each switch belongs to one bulb. It is impossible to see from one room to another. How can you find out which switch belongs to which bulb, if you may enter the room with the bulbs only once?



My solutionm to this come from reading the language very carefully. ...In an adjacent room there are 3 bulbs (all are off at the moment)

suggesting that the bulbs are not in their socket...

So i would flick ON only two of the three switches and walk into the other room where the bulbs are and insert two bulbs into their socket (may have to try several sockets). Once those two are lighted...i will know that the switch in the other room that was LEFT on OFF is for the 3rd bulb that is not lighted in the remainig socket..

Megs



If you read it more carefully, it says "each switch belongs to one bulb" meaning you should not have to assign the bulb to a socket yourself thus saving you the round trip if you use the correct solution.
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#66 roxsox

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Posted 01 August 2007 - 10:44 PM

thats easy turn on 2 swithches wait awhile turn off 1
then go into the room and feel the lightblubs and you
you will know which switch goes with which lightblub!!
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#67 aZameGa

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Posted 01 August 2007 - 11:13 PM

I agree with mdsl

I'm seriously curious why this puzzle, which has the solution included in the first post, compels so many people to create an account just to post their re-worded solution based on the same concept that a light can be on, off and cold or, off and hot.

Any ideas?



Its not only with this topic. its all over this forum. what are the chances that people who are posting Re-worded solutions havent read the solution?
for example i try not to post any solutions, unless i'have a different way of solving it...

anywayz keep up the good work people.... peace...
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#68 kentttj

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Posted 02 August 2007 - 02:44 AM

I strongly agree to the person who said that by turning on one switch you would certainly know which bulb it belongs. Simple right.
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#69 purpledots!

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Posted 07 August 2007 - 11:47 PM

omg. u people. this is a clasic riddle! you turn on one light switch and leave it on. you turn on the 2nd light switch and then turn it off 5 mins later. you leave the 3rd switch off. then you go into the other room. the light bulb that is on goes with the light switch that you turned on and left on. the light bulb that is off, but hot goes with the light switch that you turned on then turned off again. and the light bulb that is off and cold goes with the switch that was never turned on.
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#70 moNAH

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Posted 09 August 2007 - 02:10 PM

that's great one, thanks =)
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