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Guest Message by DevFuse

# Alex's 4 lightbulb problem.

2 replies to this topic

### #1 bonanova

bonanova

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Posted 07 November 2007 - 09:42 PM

You all know how to solve the 3 lightbulb problem, right?
Davey and the boys nodded in agreement.

OK then, said Alex, try this one.
You've got four switches that control four lightbulbs.
You can't see the bulbs - they're in a closed room.

You can do anything you want with the switches,
say they're marked 1, 2, 3 and 4, and then you can
go into the room and inspect the bulbs - they'll be
marked A, B, C and D.

A pint says you can't match the numbers and letters
correctly.

As usual, it was Jamie who took the bet.

Did Jamie get his pint?
• 0
The greatest challenge to any thinker is stating the problem in a way that will allow a solution.
- Bertrand Russell

### #2 unreality

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Posted 08 November 2007 - 01:25 AM

Spoiler for hint

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### #3 bonanova

bonanova

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Posted 08 November 2007 - 05:56 AM

That works. Good one!

Spoiler for hint

• 0
The greatest challenge to any thinker is stating the problem in a way that will allow a solution.
- Bertrand Russell

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