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More ways to get Braingle...

Round Table Coin Game

Logic puzzles require you to think. You will have to be logical in your reasoning.

 

Puzzle ID:#18715
Fun:*** (2.93)
Difficulty:*** (2.18)
Category:Logic
Submitted By:xpitxbullx**
Corrected By:FatHead

 

 

 



You die and the devil says he'll let you go to heaven if you beat him in a game. The devil sits you down at a perfectly round table. He gives himself and you an infinite pile of quarters. He says, "OK, we'll take turns putting one quarter down, no overlapping allowed, and the quarters must rest flat on the table surface. The first guy who can't put a quarter down loses." You guys are about to start playing, and the devil says that he'll go first. However, at this point you immediately interject, and ask if you can go first instead. You make this interjection because you are very smart and can place quarters perfectly, and you know that if you go first, you can guarantee victory. Explain how you can guarantee victory.


Answer

You place a quarter right in the center of the table. After that, whenever the devil places a quarter on the table, mimic his placement on the opposite side of the table. If he has a place to place a quarter, so will you. The devil will run out of places to put a quarter before you do.
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Comments

(user deleted)
Sep 01, 2004

excellent strategy
Jimbo*au*
Sep 19, 2004

Nice!
Poker*us*
Oct 01, 2004

I doubt he'll allow you to go first, though, if he knew what you knew...
TheGermanGemini*
Oct 01, 2004

Now what did YOU DO! Why do you have to save your eternity by playing the Devils game!? Hope it was worth it! LOL Great Teaser by the way!
dairycow7
Oct 01, 2004

I thought it was guaranteed depending on the size of the table. I was off mark, but I was impressed by the answer.
henritku
Oct 01, 2004

this one was awesome!!
sakirski*
Oct 06, 2004

Great Teaser! Good Logic!
Rowsdower*
Oct 16, 2004

Sweet! This is like a 'get out of jail free' card in monopoly, lol.
peanutAza*
Dec 06, 2004

Pretty smart but only if you're not allowed to shift up the quarters already placed..!
something*us*
Jan 26, 2005

awesome. I'll have to use that one the next time the devil asks me to play a game of "put the quarters on the table".
adoontourious**
Feb 27, 2005

I thought the table was only as big as a quarter
iblondhaha
Jun 13, 2005

wow, that's confusing . . . what if the devil didn't let you got first, is there any way to still win??? I guess you could always just spend eternity playing 'games' with the devil - sounds like fun
redraptor50*us*
Oct 01, 2005

Wow, outwitted the devil, great one,although I didn't figure it out
Chakoteya*en*
Oct 01, 2005

Obvious answer, but nice riddle nontheless.
OldChinaHand**
Oct 01, 2005

Well played...nice work. I'll have to remember this one.
OldChinaHand**
Oct 01, 2005

Well played...nice work. I'll have to remember this one.
Aarghonautsus*
Oct 01, 2005

May I play the devil's advocate?? What if the table was only big enough to hold four quarters (or 8 or 16 and so on). Then, whoever went second would win Just wondering....
jessjspieks*us*
Oct 01, 2005

Good job
AralditeAus*
Oct 01, 2005

The second person automatically looses because he can't put a quarter down until you do and is therefore the first one who can't. How's that for convoluted logic?
jimmyb**
Oct 01, 2005

Since you're so smart, you can play with your hind quarters.
On your move, you stand up as if to place a quarter on the far side of the table.
You latch onto your chair and swing it overhead bringing it down on the head of your devil friend. Your chair has been shattered and the devil is on the floor in a daze.
Like musical chairs, you take his chair and sit down.
There are no other chairs.
Isn't it great when you change the rules?
lazy-boyAus*
Oct 01, 2005

VERY SMART GOOD ONE
jbray
Oct 01, 2005

Awesome Teaser I thought the table was excatally the size of the quarter. So I was wrong But it made me think....
riddlelover**
Oct 01, 2005

Clever-very good riddle! I didn't think of it!
riddlelover**
Oct 01, 2005

Clever-very good riddle! I didn't think of the answer! (Not that that makes a difference!)
mekaboo27**
Oct 01, 2005

That was a cute one. I could not figure it out, I would rather play that game with a friend and not the devil. I am a good girl and I would hope that I would play a game like that with St. Peter or God when it is my time to go.
waternymph*
Oct 01, 2005

Em how can anyone win if you have an infinite amount of quaters? You just keep placing them down.
redneck_woman**
Oct 01, 2005

I managed to figure it out by thinking "odds and evens" ie; the first or "middle" quarter being an odd number (1) and circling it with quarters you always had a matching move to the devil's move (evens). My twisted logic anyhooo...

Jimmy B you crack me up with your answer!
thimblenogginus*
Oct 01, 2005

Something in my brain told me the answer. Isn't it nice when that happens?
Waternymph- There's an infinite amount of quarters, but not an infinite amount of table. u can't place quarters on top of each other.
foreverfree*us*
Oct 01, 2005

great teaser! i didnt get it but... waternymph, you cant keep putting quarters down cause it said no overlapping and the table is only so big

made me think! although, i think it depends on exactly how big the table is whether you can put an odd number or even number. so i think you could lose even if you go first... i dunno... who cares??? it's just a riddle
thimblenogginus*
Oct 01, 2005

Besides... when you die you are dead. That's it. Don't get your hopes up.
lindquist_25Aus*
Oct 01, 2005

Pretty good
paintballa944**
Oct 01, 2005

W@W!!!!!!!
very creative!!!!!!!!
Master_YodaAus*
Oct 01, 2005

Hey but what if you accidentally misplace a quarter ever so slighty. It never said u wouldn't make a mistake.
centerofme**
Oct 01, 2005

maybe the table is infinity sized,how would u do it then??
POPSca*
Oct 01, 2005

Just GRRRRRREAT,Loved it Good logic.
Winner4600*
Oct 01, 2005

If the table only held an even number, you wouldn't be able to put quarter in the exact center and still have an even number

oo o
ooo oo
oo o

ODD # EVEN #
Winner4600*
Oct 01, 2005

Sorry, my diagram came out wrong...
ceeyaaa**
Oct 01, 2005

Good thinking
likeaboss92*
Oct 01, 2005

It was a smart one. Great.
(user deleted)
Oct 01, 2005

I'm sorry, but there is absolutely no way that can be figured out without knowing the size of the table. It's no coincidence that NOBODY was able to figure out the answer. And if they say they did, they lied. That was a horrible riddle!
(user deleted)
Oct 01, 2005

I retract my last comment and reread the riddle. Maybe it does make sense after all.
blitzblits*
Oct 01, 2005

quote: V3ry n1c3!
(very nice)

I thought that the devil would cheat..... that rascal...
(user deleted)
Oct 03, 2005

Question -- what if the circumference of the table is only large enough to place an odd number of quarters edge to edge around the perimeter?
FulanitoGM*sv*
Oct 04, 2005

Whatever happened to good ol' fiddle-playing competitions? "The Devil went down to Georgia... He was lookin' for a soul to steal..."
precious1026Aus*
Oct 05, 2005

:roll Anything that exercise the thought process is great as far as I am concern. I love you people.
smittysgirl
Oct 05, 2005

Nice riddle
Haylie1506*
Oct 10, 2005

That was a good teaser! It was kinda hard...
(user deleted)
Oct 23, 2005

Nice puzzle and although I got it immediately, it was without completely thinking it through.

Couldn't the devil cleverly leave a vacant ring that only held an odd number of quarters? When the two of you had filled the rest of the table, he would be first to put a quarter in the empty ring.

I'm still trying to picture two infinite piles of quarters.
2 x infinity is a lot!
xpitxbullx*
Oct 29, 2005

Once a quarter is placed in the middle, no matter the size of the table, if the devil can put one down, there is a spot exactly opposite the center quarter that a quarter can be placed.
ztodd
Dec 02, 2007

sounds like hell, HA!
emu77alu02us*
Nov 25, 2008

Good One! Good thing getting into heaven doesn't have to be this complicated, though!
builderus*
Nov 25, 2008

although the game is logically completed, the devil doesn't get a say in my eternity.
104archerca*
Nov 25, 2008

The Knights were the first to play against the devil.
crazy10manAus*
Nov 25, 2008

I like story teasers like this. My first thought was to turn the table on its edge, then, being the one who places the first quarter, I wouldn't be able to place it on a vertical surface, and I would win . . . no matter the size of the table or odds or even. Is that too sneaky?
GillesAca*
Nov 25, 2008

Too difficult for me
bradon182001*us*
Nov 25, 2008

Hmmm. Have to agree with you Gilles. Guess I'm just not logical.Thanks for posting, though.
auntiesisAus*
Nov 25, 2008

Hope I'm never in that position, because I'll never remember how to win over that ol' devil. Just too hard for me.
FatHeadAus*
Nov 25, 2008

For Go and for Dots-and-Boxes, this strategy works perfectly against a lesser player, or sometimes a stronger player who gives you a handicap in points, unless they know how to overcome it - which some do.

Good teaser.
adam213Aus*
Nov 25, 2008

I'm not so sure about this teaser...
(user deleted)
Nov 25, 2008

the devil isn't a "guy", so you automatically lose....OR you have to put down your infinite number of quarters until you run out of table space......OR you put one down and then pick it back up, over and over!!!! (for infinity...ugh!)

i'm surprised no one said that yet!
cwjakesteelAjm*
Nov 25, 2008

I see your logic... but why the devil?
EliosAus*
Nov 25, 2008

Interesting! I'm still not convinced that this'll work.. gonna have to find a round table and a LOT of quarters! Still, when the devil shows up at my door, at least I'll have something to try.
UptheHillA*
Nov 25, 2008

NICE TOO!!!
plokolplokph
Nov 25, 2008

VERY NICE...
leroy_h*
Nov 26, 2008

NO OFFENSE MEANT BUT THIS MADE NO SENSE TO ME
avonmaAus*
Nov 27, 2008

I'm not sure of the writer's logic; but it sounds interesting...
builderus*
Nov 25, 2011

cute riddle, simple. BTW, the devil isn't the One who decides if you go to heaven - just saying.
Mandy7us*
Nov 26, 2011

haha nice one, even if i dont believe in the devil and heven and stuf
gearingUp
May 04, 2012

I think this does not always hold as sometimes the symmetric position does not exist:

For instance, consider the case when the whole table is filled up with coins except for an annulus one coin wide on the outer diameter (OD) of the table. If the devil keeps placing coins spaced such that only an odd number of coins fit on the OD, a symmetric condition does not exist. In this case, a draw is guaranteed. So, throughout the game, the devil will place coins so as to prevent symmetry and he will not lose. Anybody disagree?
eighsseAus*
Aug 18, 2013

I don't understand what everyone is saying about this "1-quarter-wide ring" and all the stuff about an odd number of coins...
I think the teaser is brilliant (I did get it right), and I don't see any way that it could possibly NOT work. After each quarter the devil places, you place an opposite quarter. There is no way, on ANY turn, that he can place a quarter, whose opposite space is not completely clear.
I think this how I need to say it: Consider your outer ring that can only fit an odd number of coins. An odd number might be the MAXIMUM coins that can fit, but if you oppose his moves, you will be upsetting that pattern. (Think about it: if an odd number is going to fit perfectly into the ring, then directly opposite his coin SHOULD be not a full coin, but the point where two coins meet... YOU, however are putting a full coin there, ruining this perfect fit.)
It will ALWAYS be centrally symmetrical after your turn. And when it is symmetrical, there is always either:
1. No place for a quarter
2. At least 2 places for a quarter
Babe*
Nov 25, 2014

A good one to make people think, but easy to figure out. It can be a bet between any two people. It does not have to be a devil. If he initiated the game, he probably knew the answer also and therefore you would not get to go first. Oh well, it is just a teaser.
HABS2933Aca*
Nov 25, 2014

I agree with Babe, there is no way the devil (having suggested the game) or anyone with half an active brain cell would agree to letting their opponent go first.
Boldcommander*
Nov 25, 2014

Well, the OP never mentioned the size of the table, so I assumed the table was the size a single quarter and that whoever goes first instantly wins.
xpitxbullx*
Nov 26, 2014

As long as the table can hold at least one quarter then the size of the table is irrelevant.



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