Ancient Chestnut Puzzles

[OcularGold]

Apparently, the minotaur doesnt check the visitor submitted puzzles often enough. all three, along with the solutions, appear there.

[This message has been edited by OcularGold (edited 06-19-2000).]

[Dragon Phoenix]

Please read the introduction: he actually states that these are submitted more often than anything else, and that he is just showing them to kill them off.

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XXXXXX rude sig censored by forum monitor

[IrishJoe]

And a well-deserved killing, it seems.

[Tom]

Does the solution to the 3 houses, 3 utilities appear here somewhere? Other than just the statement "It can't be done"?

I'd be interested to see a proof that it can't be done.

[Quailman]

I think araya or someone has submitted a proof that it can't be done. The only possibility I see is if a utility company gets a right-of-way from one of the homeowners to run a line through his basement.

[daniel801]

it can be done in 3d (utilities)

[NC]

The solution i've seen for the utilities problem involves drawing the houses and utilities on a piece of paper.The paper is then folded 3 times between the houses and utilities,and one utility supplies all 3 houses per fold.

[GAH]

Ancient Chestnut #2:

Proof that it can't be done: There's a theorem in graph theory that states that
"A graph is planar if and only if it does not have K_5 or K_3,3 as a portion of it."

The problem of the houses and utilities falls into the category of
drawing a K_3,3 graph. As such, it is not a planar graph.

('Planar' means that it can be drawn without the lines criss-crossing;
'K_m' is a complete graph of m vertices;
'K_m,n' is a complete bipartite graph of m to n vertices).

GAH

[Ghost Post]

Everyone should check out
http://mathworld.wolfram.com/UtilityGraph.html

for a disussion of this very problem.

[Ghost Post]

i would have to agree with you if electricity wasn't one of the utilities. but, as it is, why is the following solution wrong (bear in mind that we were asked "is it possible to connect each house to all 3 utilities...".):

connect the Gas to all three houses from below. then connect the water to all three houses from above (line A going right, up and left again to the green house, line B going a bit down, more to the right than line A, up over line A, left again, over line A, and down to the blue house, etc...). finally connect the electricity to the white house in the following way: go down, left (behind the gas), up and a bit right to get to the white house. all you need to do now is to connect the white house to the blue house and the blue house to the green one. as we are dealing with electricity it is possible to connect the houses to each other and still follow the directions of the puzzle.
as you can see - the lines don't X.

[Ghost Post]

Ancient Chestnut #1:

There is no missing dollar. The dollar is hidden inside the question. And the question just confuses the reader.

$30 = The manager kept $25 + $3 was returned to the salesmen + $2 is with the bellhop.

If you see from a different angle, the salesmen paid ONLY $27 (and NOT $30) which is nothing but the $25 which is with the manager and $2 which is with the bellhop

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[This message has been edited by Subodh (edited 06-23-2000).]

[Oracle-UK]

Now that you can get electricity and gas from the same supplier (in the UK anyway)- the puzzle can now easily be solved!

[Kay Marshall]

About the GRY puzzle, when I first heard this, I did extensive research on it. It appears that the wording of the puzzle is critical, and the minotaur has the wording wrong. (sorry!) The original puzzle was, "Think of words ending in "gry". Angry and Hungry are two of them. There are only three words in the english language. What is the third word? The word is something everyone uses every day. If you have listened carefully, I have already told you what it is."
The answer, of course, is "LANGUAGE".
The wording of the puzzle is meant to mislead, and the posted puzzle in the labyrinth doesn't word the puzzle correctly. This puzzle was originally posted many many years ago in AOL, and has reappeared in various reincarnations (and messed up re-wordings) ever since. (I believe this, because I did HOURS of research in the library on this years ago!)

[Murray]

[stoatboy]

I believe, as an alternative answer, that just "gry" is a word, in and of itself. Not a common word, nor something that I use every day. But it does end in -gry.

[Ghost Post]

I am in the "can do it" camp on the utility puzzle. Run the gas line up the left side and behind the houses. Run the electric wire down and around the water utility, up the right side, and over the top of the houses. Run a water line from the utility to each house. There are other ways to do, but as Ori said, this is the most practical.

[Puzzlanian]

"Gry" is infact a word. It is a unit of measurement that is about as long as the bridge of your nose.

[ZenBeam]

Another solution for Chestnut #2, the three house - three utility puzzle

Use insulated copper pipes for the gas and water lines, and couple the two electric paths one to each pipe (electricity requires two conductive paths). When you hook up both gas and water, you automatically have electricity as well. Just use a length of insulating plastic pipe right inside each house, so the gas and water aren't electrified inside the house. This works with any number of houses.


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The "Zen" part of your name is sort of wide and heavy, a bit like a pyramid, but it looks...dignified?
The "Beam" part is like yellow light radiating from open eyes or an open source; it looks pleased with itself. -- tiny cow
It is too clear, and so it is hard to see.

[groza528]

What if you actually ran the electric wires on the inside of the water pipes? If insulated well, the electricity and water could both travel through one pipe simultaneously. I don't believe that qualifies as crossing.