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Peegee
05-09-2006, 02:53 AM
I'd appreciate it if after this puzzle is 'done' we continue.

http://img354.imageshack.us/my.php?image=puzzle14qd.gif

Draw a line from A to XY&Z, B to XY&Z and C to XY&Z without any of the lines intersecting.

Which means you can't overlap and say 'it works in 3D'.

Go.

Also, if you claim it's not possible, provide proof :)

Tama2
05-09-2006, 02:57 AM
do they gotta be striaght?

edit: If not I did it.

Peegee
05-09-2006, 03:50 AM
They don't.

And you did it? Pics.

Tama2
05-09-2006, 04:36 AM
Dammit, now I have to use paint. grrrr

Dr Unne
05-09-2006, 05:13 AM
Informal proof that it's impossible. (This is not rigorous, so I may just be missing a solution, but oh well.) See attached image. It should be clear that you can move the nodes around without affecting anything, since we're not limited in the length or direction of our lines.

Drawing lines from A to X,Y,Z and from B to X,Y,Z will always divide the plane into three areas: two 4-sided polygons which share two sides (blue and green in my attachment), and an area outside those polygons (white).

For proof that it will always form these areas: Take A and B, and any two of X,Y,Z, let's say X and Y, though it doesn't matter. Connecting them as per the original problem will always form a quadrilateral. This should be obvious; if you connect four points with four lines, two lines touching each point, you form a 4-sided polygon AXBY. Now you have one leftover node (Z). You can either place it inside or outside the polygon, nowhere else. If you place it inside, the two lines from A and B will split the polygon into two pieces, which leaves you with two 4-sided polygons sharing two sides. If you place the node outside, the two lines from A and B will form a second polygon which borders the first (sharing two sides). Either way, you end up with two enclosed 4-sided polygons sharing two sides, as per my attachment.

If C is enclosed in AZBY (blue) it can't reach X. If C is enclosed in AYBX (green) it can't reach Z. If C is outside them both (white) it can't reach Y. Forming the two 4-sided polygons from nodes A,B,X,Y,Z or A,C,X,Y,Z or B,C,X,Y,Z all reduce to the above scenario. There are no other possibilities; therefore the original problem is impossible.

EDIT: Clearly if you can show any way that you can connect two of A,B,C with three of X,Y,Z without forming two 4-sided polygons that share two edges, then what I've posted will be disproved.

Peegee
05-09-2006, 12:30 PM
You forgot one thing.

A new puzzle!

(btw Dr Unne got it)

-N-
05-09-2006, 12:32 PM
Aw. Yeah, I linked my math major buddy to it and he told me it was impossible. He signed off before I could ask him for a proof, though. Guess Unne got it first.

Loony BoB
05-09-2006, 01:25 PM
Puzzles that ask you to do something that can't be done are annoying, even if the answer is simple. I prefer being challenged to do something that is possible but also difficult. That's a real challenge. None of this "prove that it can't be done" nonsense - I stopped doing that crap when I left High School, thankyaverymuch. No need to spend long times typing out a proof like that above when you could spend your time doing more productive and mind-challenging problems that actually have a solution. Proofs wore the most boring thing about Calculus by a long, long way. I don't care how much intelligence is required, I much prefer a sense of achievement in proving something can be done than proving something can't be done. Give us a real puzzle!

Shaun
05-09-2006, 01:42 PM
That first puzzle very obviously couldn't be done without the Z-axis present. But I agree BoB. :p I'd find one myself, but I really can't be bothered right now.

Dr Unne
05-09-2006, 10:31 PM
You forgot one thing.

A new puzzle!

(btw Dr Unne got it)

Um. I found this on a website. Don't cheat by googling it.

After a particularly taxing night of solving logic puzzles and riddles, your brain suddenly shuts down and you find yourself in what you can only hope to be a bizarrely relevant dream. Seated beside a set of pearly gates is the patient-looking figure of St. Peter, white robes and all. "We're glad you could make it, but before you go in, there's just one little question you have to answer," says Peter, and you begin to suspect that this will be a 'thinking' type of question.

"How many angels can dance on the head of a pin?" He raises a hand to point to an inscription on the gates. "The answer lies therein. Each is accounted for, and the further you go, the more you'll get. Take your time; you have plenty of it." After a few cautious steps on the cloud-like floor, you approach the gate and read:

How wondrous too is truth received
For him who'd defy verity
As hope the sick soothes even sates
So benign the uncertain's made

Levian
05-09-2006, 10:35 PM
I hate it when riddles are mocking me for having English as a second language with words like verity and benign.

Dr Unne
05-09-2006, 10:50 PM
Most native English speakers (Americans anyways) likely have no idea what verity means, so don't worry about it.

Cz
05-09-2006, 10:52 PM
Is the answer ten? I'm not entirely sure what I'm looking for, but from what I can grasp of the puzzle, that would be a logical solution.

Peegee
05-10-2006, 12:42 AM
Dr Unne still hasn't announced whether Cz is right, but I found this:


A monk lives at a temple at the bottom of the hill. Every week, he starts at sunrise and climbs up to the temple at the top of the hill, getting there exactly at sunset. He spends the night at the temple in meditation, then the next morning starts again at sunrise, and walks down the hill to the lower temple, arriving at sunset. He doesn't walk at a steady pace, and often will stop to eat some of the dried fruit he has, or rest, walk slower, etc.

Assuming sunrise and sunset are exactly the same on both days, and that the there is only one path between the temples, will the monk be at the same place at the same time at some point on both days? Prove why he must, or why he won't necessarily, 2 easy ways to explain it.

-N-
05-10-2006, 02:24 AM
Puzzles that ask you to do something that can't be done are annoying, even if the answer is simple. I prefer being challenged to do something that is possible but also difficult. That's a real challenge. None of this "prove that it can't be done" nonsense - I stopped doing that crap when I left High School, thankyaverymuch. No need to spend long times typing out a proof like that above when you could spend your time doing more productive and mind-challenging problems that actually have a solution. Proofs wore the most boring thing about Calculus by a long, long way. I don't care how much intelligence is required, I much prefer a sense of achievement in proving something can be done than proving something can't be done. Give us a real puzzle!Looks like someone got frustrated with his limited intelligence. :p

edit: PG's puzzle:
http://www.geocities.com/princeofdarknez/pg.PNG
This puzzle scenario can simply be rephrased as a scenerio where two monks walk from each end to the other, and ask whether or not they cross paths. This is obviously true. Just imagine the red path to be the monk on one day and the blue path to be the monk on the next day. It makes sense.

Dr Unne
05-10-2006, 02:52 AM
Is the answer ten? I'm not entirely sure what I'm looking for, but from what I can grasp of the puzzle, that would be a logical solution.

It's right, but the interesting part is how you get the answer. Someone can come up with the whole answer.

-N-
05-10-2006, 04:46 AM
How ONEdrous TWO is truTH REEceived
FOUR him who'd deFI VErity
As hope the SIX ootheS EVEN sEIGHTs
So beNINE the uncerTEN's made

I should have known it would be something like this coming from Unne. :p

edit: I guess I owe an explanation of what made me think this way. St. Peter says "therein", which makes me think of words inside words. He also says "each is accounted for", meaning the final number should be counted up to in the riddle. "Take your time" - all I had to do was start saying it out slowly and bam. In the verse section, the last couplet clued me in to the indirect nature of finding the clues - the general idea of the truth appearing, truth defying, an uncertain answer as benign, something I dunno, it made sense, shut up I'm not sober. :p

Cz
05-10-2006, 04:51 PM
How ONEdrous TWO is truTH REEceived
FOUR him who'd deFI VErity
As hope the SIX ootheS EVEN sEIGHTs
So beNINE the uncerTEN's made

I should have known it would be something like this coming from Unne. :p

edit: I guess I owe an explanation of what made me think this way. St. Peter says "therein", which makes me think of words inside words. He also says "each is accounted for", meaning the final number should be counted up to in the riddle. "Take your time" - all I had to do was start saying it out slowly and bam. In the verse section, the last couplet clued me in to the indirect nature of finding the clues - the general idea of the truth appearing, truth defying, an uncertain answer as benign, something I dunno, it made sense, shut up I'm not sober. :pYeah, that was more or less how I got it. Lev's benign comment alerted me to the words-within-words thing, but I wasn't entirely sure what the final total was supposed to be. "Ten's made" sounded conclusive enough, so I went for that.

Sorry, should've explained myself earlier. :)

As for PG's puzzle, I agree with Neel's solution.

-N-
05-11-2006, 11:05 PM
Um, I don't have any puzzles, other than weird physics problems. :p

GhandiOwnsYou
05-12-2006, 09:06 AM
You might want to add to that first puzzle that the points ABC and XYZ are considered lines themselves. By making them mere markers (by that i mean, that you could pass through one point on the way to another, so long as you don't touch another connecting line) it actually is possible. but yeah, otherwise, you can only knock all but one line out. Not trying to nitpick, there are just tons of problems out there that require a backhanded solution like that.

http://img.photobucket.com/albums/v332/GhandiOwnsYou/pzzlesolution.jpg

anywho, run this one. should be fairly simple and make room for a harder puzzle. Using a three gallon and a seven gallon container, and making no marks on the container (no saying "mark three gallons on the seven..." etc.) measure 5 gallons.

Alos, simple enough, arrange 12 lines of equal size and length, create 6 polygons of equal size and shape.

Raistlin
05-12-2006, 02:58 PM
SA: You have two lines from C to X and none from C to Y.

for your problem: fill the 3 gallon container twice and dump it into the 7 gallon one, making 6 gallons. Then fill the 3 gallon container once more and dump what you can into the 7, leaving 2 gallons in the 3. Dump out the 7 and pour the 2 gallons into it. Then just fill up the 3 gallon container again and dump it into the 7. 5 gallons.

I don't have time to look up a puzzle right now, so someone else can post one. :p

Peegee
05-13-2006, 12:01 AM
You might want to add to that first puzzle that the points ABC and XYZ are considered lines themselves. By making them mere markers (by that i mean, that you could pass through one point on the way to another, so long as you don't touch another connecting line) it actually is possible. but yeah, otherwise, you can only knock all but one line out. Not trying to nitpick, there are just tons of problems out there that require a backhanded solution like that.

http://img.photobucket.com/albums/v332/GhandiOwnsYou/pzzlesolution.jpg

anywho, run this one. should be fairly simple and make room for a harder puzzle. Using a three gallon and a seven gallon container, and making no marks on the container (no saying "mark three gallons on the seven..." etc.) measure 5 gallons.

Alos, simple enough, arrange 12 lines of equal size and length, create 6 polygons of equal size and shape.

xD

Dr Unne
05-13-2006, 12:33 AM
Alos, simple enough, arrange 12 lines of equal size and length, create 6 polygons of equal size and shape.

-N-
05-13-2006, 04:06 AM
Yeah I was confused about that one because you don't need 12 lines.

GhandiOwnsYou
05-13-2006, 10:11 AM
shnap. my bad for insomniac posting. no overlapping the lines. Call me a retard and shoot me in the face.

fire_of_avalon
05-13-2006, 02:37 PM
anywho, run this one. should be fairly simple and make room for a harder puzzle. Using a three gallon and a seven gallon container, and making no marks on the container (no saying "mark three gallons on the seven..." etc.) measure 5 gallons.
That was in Die Hard 3!

Raistlin
05-13-2006, 02:46 PM
anywho, run this one. should be fairly simple and make room for a harder puzzle. Using a three gallon and a seven gallon container, and making no marks on the container (no saying "mark three gallons on the seven..." etc.) measure 5 gallons.
That was in Die Hard 3!
No, Die Hard used 5 and 3 gallon buckets to make 4 gallons, and the solution for that is a bit different. :p For that one you simply pour the 5 gallon into the 3 gallon, leaving 2 gallons in the 5 gallon. Pour the 2 gallons into the 3. Then fill the 5 up again and pour what you can into the 3 (one gallon), leaving 4 gallons in the 5 gallon container.

That bugged me in Die Hard because they didn't explain the process fully. So I had to mess around with the problem for a few minutes until I figured it out myself.

fire_of_avalon
05-13-2006, 03:06 PM
Shut up! >:O

Dr Unne
05-14-2006, 02:39 AM
shnap. my bad for insomniac posting. no overlapping the lines. Call me a retard and shoot me in the face.

http://hexaflexagon.sourceforge.net/template.jpg