Brain teaser time!!

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YOyoYOhowsDAjello

Moderator<br>A/V & Home Theater<br>Elite member
Aug 6, 2001
31,205
45
91
Ok, now I'm thinking

#5 gets screwed when it's down to 2 pirates, so he needs to vote before that
#4 gets screwed when it's down to 3 pirates, so he needs to vote before that

When it's down to 4 pirates, No. 2 just needs to give 1 gold to No. 4 to get his vote because he'd get nothing in the next vote.

If it goes one more round, No. 3 and No. 4 get nothing.

I just need to offer them something to get their votes.

New answer:

No.1 : 98
No.3 : 1
No.4 : 1

This seems too simple :p

EDIT: I just screwed up the numbers at the end but came to the same conclusion you did Tux.

I meant to write:

When it's down to 4 pirates, No. 2 just needs to give 1 gold to No. 4 to get his vote because he'd get nothing in the next vote.

If it goes one more round, No. 3 and No. 5 get nothing.

I just need to offer them something to get their votes.

New answer:

No.1 : 98
No.3 : 1
No.5 : 1
 

YOyoYOhowsDAjello

Moderator<br>A/V & Home Theater<br>Elite member
Aug 6, 2001
31,205
45
91
I hope the pirates were patient and would have given me the time to think about the problem :laugh:
 

puffff

Platinum Member
Jun 25, 2004
2,374
0
0
suppose there are 2 pirates. pirate 1 (the senior) would just give all the gold coins to himself, and none to pirate 2. he would vote for it, and therefore win.

now take the the example of 3 pirates. pirate 1 (again the most senior) knows he must gain the vote of at least one other pirate. therefore, he must give pirate 3 (the least senior) only 1 gold coin. reasoning? if pirate 3 votes against this proposal, pirate 1 is gone, and we're down to the two pirate situation where pirate 2 gets everything.

take the situation with 4 pirates. again, pirate 1 must gain the vote of at least one other pirate. simplest and cheapest way? pay off pirate 4 with one gold coin, since thats the most he's gonna get in one to three pirate situations

finally, 5 pirates. pirate one must gain the vote of two others. the cheapest guys to pay off would be pirate 4 and 5. give one to pirate 5, and one to pirate 4, and keep the rest.

so, in conclusion, if you are the most senior pirate, you could walk away with 98 of the 100 gold coins.
 

mobobuff

Lifer
Apr 5, 2004
11,099
1
81
Originally posted by: puffff
suppose there are 2 pirates. pirate 1 (the senior) would just give all the gold coins to himself, and none to pirate 2. he would vote for it, and therefore win.

now take the the example of 3 pirates. pirate 1 (again the most senior) knows he must gain the vote of at least one other pirate. therefore, he must give pirate 3 (the least senior) only 1 gold coin. reasoning? if pirate 3 votes against this proposal, pirate 1 is gone, and we're down to the two pirate situation where pirate 2 gets everything.

take the situation with 4 pirates. again, pirate 1 must gain the vote of at least one other pirate. simplest and cheapest way? pay off pirate 4 with one gold coin, since thats the most he's gonna get in one to three pirate situations

finally, 5 pirates. pirate one must gain the vote of two others. the cheapest guys to pay off would be pirate 4 and 5. give one to pirate 5, and one to pirate 4, and keep the rest.

so, in conclusion, if you are the most senior pirate, you could walk away with 98 of the 100 gold coins.

That does make sense, but for some reason I think you're missing something.
 

YOyoYOhowsDAjello

Moderator<br>A/V & Home Theater<br>Elite member
Aug 6, 2001
31,205
45
91
Originally posted by: mobobuff
Originally posted by: puffff
suppose there are 2 pirates. pirate 1 (the senior) would just give all the gold coins to himself, and none to pirate 2. he would vote for it, and therefore win.

now take the the example of 3 pirates. pirate 1 (again the most senior) knows he must gain the vote of at least one other pirate. therefore, he must give pirate 3 (the least senior) only 1 gold coin. reasoning? if pirate 3 votes against this proposal, pirate 1 is gone, and we're down to the two pirate situation where pirate 2 gets everything.

take the situation with 4 pirates. again, pirate 1 must gain the vote of at least one other pirate. simplest and cheapest way? pay off pirate 4 with one gold coin, since thats the most he's gonna get in one to three pirate situations

finally, 5 pirates. pirate one must gain the vote of two others. the cheapest guys to pay off would be pirate 4 and 5. give one to pirate 5, and one to pirate 4, and keep the rest.

so, in conclusion, if you are the most senior pirate, you could walk away with 98 of the 100 gold coins.

That does make sense, but for some reason I think you're missing something.

I think the only issue is that it's cheaper to pay off #3 and #5 in the last step rather than #4 and #5 since #4 can expect to be paid 1 gold in the next round, so you'd have to pay him more than that to ensure that he votes for your plan.

#3 and #5 would get nothing if it carried on for one more round though, so those are the cheapest to buy off.
 

mobobuff

Lifer
Apr 5, 2004
11,099
1
81
Originally posted by: YOyoYOhowsDAjello
Originally posted by: mobobuff
Originally posted by: puffff
suppose there are 2 pirates. pirate 1 (the senior) would just give all the gold coins to himself, and none to pirate 2. he would vote for it, and therefore win.

now take the the example of 3 pirates. pirate 1 (again the most senior) knows he must gain the vote of at least one other pirate. therefore, he must give pirate 3 (the least senior) only 1 gold coin. reasoning? if pirate 3 votes against this proposal, pirate 1 is gone, and we're down to the two pirate situation where pirate 2 gets everything.

take the situation with 4 pirates. again, pirate 1 must gain the vote of at least one other pirate. simplest and cheapest way? pay off pirate 4 with one gold coin, since thats the most he's gonna get in one to three pirate situations

finally, 5 pirates. pirate one must gain the vote of two others. the cheapest guys to pay off would be pirate 4 and 5. give one to pirate 5, and one to pirate 4, and keep the rest.

so, in conclusion, if you are the most senior pirate, you could walk away with 98 of the 100 gold coins.

That does make sense, but for some reason I think you're missing something.

I think the only issue is that it's cheaper to pay off #3 and #5 in the last step rather than #4 and #5 since #4 can expect to be paid 1 gold in the next round, so you'd have to pay him more than that to ensure that he votes for your plan.

#3 and #5 would get nothing if it carried on for one more round though, so those are the cheapest to buy off.

I think that completes it. The method of making sure #4 votes yes.
 

alrocky

Golden Member
Jan 22, 2001
1,771
0
0
Originally posted by: Captante
Considering the terms I'd go with 20 each.
I'd like to think this is the correct answer. Oddly enough if it's not the correct answer, I think the 4th and 5th least senior pirates carry a lot more power than most of you think. Remember that if a proposal is voted down, someone dies, and dying is worst than getting nothing. Off the top of my head I'm thinking #1 gets 1, #2 & #3 get 0, #4 gets 49, and #5 get 50.

 

cjbee

Member
Mar 11, 2005
125
0
0
Why would the division of gold coins matter if you're stuck on an island? I'd start hunting for food.
 

Vegitto

Diamond Member
May 3, 2005
5,234
1
0
Give all of them 25 coins, talk to each of them separately and tell them you'll kill all the others at night and bring them half of the loot, giving them 62.5 coins. What you don't tell them is that you actually kill all of them.
 

alrocky

Golden Member
Jan 22, 2001
1,771
0
0
Originally posted by: chuckywang
I saw this on another message board:
(The pirates are all extremely logical and greedy, including you, and all want to live.
One step back, #1 to #5. He gives 1 coin to #3, #5 and 98 for himself. End?
Who the heck is going to vote to receive only one coin?

The 'nominally fair value' for is 20 gold pieces per pirate. Because they're greedy they'll opt for any division plan that provides a reasonable chance of them getting more than 20 gold pieces. They should not vote "yes" for any plan that has 100% certainty of getting less than 20 gold pieces.

Senior pirate (#1) proposes they vote on a slate of several distribution plans as follows:

A) 20 each
B) 25:25:25:25:0
C) 34:33:33:0:0
D) 50:50:0:0:0
E) 100:0:0:0:0
F) 40:30:20:10:0
G ...

He lists 6 to 10 plans. The plan that receives at least 3 votes is the distribution plan and the pirates draw straws to determine their cut. (If the pirates vote 2:2:1, then the plan with only one vote is tossed and the pirates re-vote on the two plans. It can get a tad complicated if the vote is 2:1:1:1 but it can be resolved.)

The 5 straws are labeled with the gold pieces awarded as shown above in each of the plans. Plan "F" gives each pirate a 3 out of 5 chance of receiving at least 20 gold pieces, the 'nominally fair value' distribution.
 

YOyoYOhowsDAjello

Moderator<br>A/V & Home Theater<br>Elite member
Aug 6, 2001
31,205
45
91
Originally posted by: alrocky
Who the heck is going to vote to receive only one coin?

The guys who know that if it goes one more round they'll get nothing
 

alrocky

Golden Member
Jan 22, 2001
1,771
0
0
Originally posted by: YOyoYOhowsDAjello
Originally posted by: alrocky
Who the heck is going to vote to receive only one coin?

The guys who know that if it goes one more round they'll get nothing
I'm greedy pirate #5! If you don't offer me a chance at least the nominally fair value of 20 gold pieces I'll vote you dead. I may be greedy and broke but you'll be dead and broke. Being greedy does not mean I'll settle for only one if the alternative is none. Being greedy means getting at least 20 and a shot of getting more than that. Being alive is more important than gettting only one coin.

 

WHAMPOM

Diamond Member
Feb 28, 2006
7,628
183
106
Originally posted by: chuckywang
I saw this on another message board:
Five pirates on an island have one hundred gold coins to split among themselves. They divide the loot as follows: The senior pirate proposes a division, and everyone votes on it. Provided at least half the pirates vote for the proposal, they split the coins that way. If not, they kill the senior pirate and start over. The most senior (surviving) pirate proposes his own division plan, and they vote by the same rules and either divide the loot or kill the senior pirate, as the case may be. The process continues until one plan is accepted. Suppose you are the senior pirate. What division do you propose? (The pirates are all extremely logical and greedy, including you, and all want to live.)

That is simple, as senior pirate, you propose to divide the treasure between yourself and two others.
 

dxkj

Lifer
Feb 17, 2001
11,772
2
81
I am logical and know that 1 coin isnt worth it, Id vote no for anything less than 20
 

Lonyo

Lifer
Aug 10, 2002
21,938
6
81
Originally posted by: dxkj
I am logical and know that 1 coin isnt worth it, Id vote no for anything less than 20

Um, you get nothing if you don't take 1 coin, or you might die, assuming you are #3 or #5.
 

bersl2

Golden Member
Aug 2, 2004
1,617
0
0
Wikipedia article

The whole point of the game is moot, because these pirates are Homo economicus, not Homo sapiens. A true pirate is not a rational creature! The other pirates would gut the senior pirate just because they could. :D
 

her209

No Lifer
Oct 11, 2000
56,336
11
0
Originally posted by: dxkj
I am logical and know that 1 coin isnt worth it, Id vote no for anything less than 20
The only pirate that is deserving of more than 20 coins is me aye matey? Are we savy?

Arggg. : Pirate ;