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OttifantSir
September 27th, 2007, 11:54 AM
This is a problem for which I have no answer, which is why I post it here. I have learned that among you here, there is a lot of brainpower, and while I have shown this problem to several dozens of people, all trying their best to solve it, noone has done it yet.

Attached is a picture depicting the problem as it was presented to me. Along with this picture, there came instructions:

1-All houses(1-3) must have W(ater), P(ower) and S(ewer).
2-All houses must receive this directly from source
3-No two lines/feeds from W,P or S must cross.

I really hope one of you may be able to solve this problem. Either through brute-forceing it or mathematically analyze it.

PS: Forgive the crudeness of the picture. Hard to draw pretty with a mouse.

init1
September 27th, 2007, 05:57 PM
This is a problem for which I have no answer, which is why I post it here. I have learned that among you here, there is a lot of brainpower, and while I have shown this problem to several dozens of people, all trying their best to solve it, noone has done it yet.

Attached is a picture depicting the problem as it was presented to me. Along with this picture, there came instructions:

1-All houses(1-3) must have W(ater), P(ower) and S(ewer).
2-All houses must receive this directly from source
3-No two lines/feeds from W,P or S must cross.

I really hope one of you may be able to solve this problem. Either through brute-forceing it or mathematically analyze it.

PS: Forgive the crudeness of the picture. Hard to draw pretty with a mouse.
I can't do it. I think it may be impossible. I'll try to prove it either way.

Chilli Bob
September 27th, 2007, 06:52 PM
I remember this from my school days. I'm sure it can be done. Will have a look at it after work today.

lisati
September 27th, 2007, 06:54 PM
The puzzle looks vaguely familiar, but I can't remember the solution.

monsieurdozier
September 27th, 2007, 09:37 PM
The attached image is the way I've always done it, but I've never heard this puzzle presented with that second rule you've included. Other than that, this website solves it all.

http://mathforum.org/dr.math/faq/faq.3utilities.html