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# You live in Killville. Can you stay alive?

Best Answer Writersblock , 10 October 2007 - 11:14 PM

Hmmm. This is an ambiguous question I think. I read it originally as surviving one encounter, but it can also be understood to be the "last man standing."

### #11

Posted 17 January 2008 - 10:13 PM

1) If people only meet in pairs 1 time, you have a 50/50 chance to survive (10K, 8K2P, 6K4P, 4K6P, 2K8P, 10P)

2) If people meet over and over and over until people stop getting killed, you have 0 Killers. As a Pacifist, you have a 31.25% chance of survival... someone else want to double check the math for me? I did it quick, dirty, and am still human.

### #12

Posted 21 January 2008 - 06:48 AM

Killers eliminate themselves pairwise. So an even number of killers eventually eliminate themselves - you'd want to be a pacifist then.

An odd number of killers eventually become a single killer that eventually eliminates all the pacifists - you want to be a killer then.

*The greatest challenge to any thinker is stating the problem in a way that will allow a solution.*

- Bertrand Russell

### #13

Posted 13 February 2008 - 03:03 AM

Spoiler for solution

Wouldn't P meets K be the same as K meets P? One of them should be eliminated from the probability equation, making P the better choice.

P meets P - P population stays same

K meets K - K population minus 2

P meets K - P population minus 1

In one out of three meetings One P will die.

In one out of three meetings Two K will die.

### #14

Posted 13 February 2008 - 06:03 AM

Think what it means to survive.Wouldn't P meets K be the same as K meets P? One of them should be eliminated from the probability equation, making P the better choice.

P meets P - P population stays same

K meets K - K population minus 2

P meets K - P population minus 1

In one out of three meetings One P will die.

In one out of three meetings Two K will die.

It's more than just getting past the first encounter.

What happens when an indefinite amount of time has gone by?

*The greatest challenge to any thinker is stating the problem in a way that will allow a solution.*

- Bertrand Russell

### #15

Posted 13 February 2008 - 06:18 AM

** your only chance for survival is to be a pacifist and the even number of killers kill each other off first.

Situation I - When a pacifist meets a pacifist, nothing happens.

Situation II - When a pacifist meets a killer, the pacifist is killed.

Situation III - When two killers meet, both die.

As a Pacifist, your only chance of survival (over an infinite period) would be that 5 pairs of killers met before your ticket was punched.

As a Killer, you would have 9 other killers out there... best case would be that 4 pairs of killers meet but this would still leave one other killer (your nemisis) which you would eventually run into. (assuming there must be a meeting)

**Edited by Bad Dog, 13 February 2008 - 06:19 AM.**

### #16

Posted 13 February 2008 - 06:26 AM

Hint 1: What does it mean to survive?

Hint 2: Would the result be different if Killville were populated by 11 killers and 11 pacifists?

Reply --

1.) to survive means that you have no chance of being killed by a killer ... (assumed)

2.) result dif with 11 Killers and 11 Pacifists: Absolutely... odd number of killers would mean that one will always be around to kill and he would be the last man standing... so this would mean that it is better to be a killer and hope your the one that never meets another killer.

### #17

Posted 28 February 2008 - 06:35 PM

### #18

Posted 28 February 2008 - 08:50 PM

Therefore Ps survive

Meanwhile

There are road signs for this - and then you just have LOL

### #19

Posted 29 February 2008 - 01:48 AM

### #20

Posted 02 March 2008 - 06:48 PM

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