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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."

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#1 bonanova

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Posted 10 October 2007 - 11:52 AM

You live in Killville - a town populated by 10 killers and 10 pacifists.

When a pacifist meets a pacifist, nothing happens.
When a pacifist meets a killer, the pacifist is killed.
When two killers meet, both die.

Assume meetings always occur between exactly two persons
and the pairs involved are completely random.

Are your odds of survival better if you are a killer? or a pacifist?
Or does it matter?

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

#2 Writersblock

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Posted 10 October 2007 - 06:50 PM

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#3 brhan

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Posted 10 October 2007 - 07:48 PM

Not sure if this approach is correct

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#4 unreality

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Posted 10 October 2007 - 08:20 PM

killers have 1/19 better chance of survival


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#5 bonanova

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Posted 10 October 2007 - 08:56 PM

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?
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- Bertrand Russell

#6 Writersblock

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Posted 10 October 2007 - 11:14 PM   Best Answer

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."

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#7 willy

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Posted 11 October 2007 - 03:55 PM

since all 3 possible meetings [p-p, p-k, k-k] are equally likely to begin with, suppose after 3 such meetings each type has taken place. at that point there would be 2 dead killers and one dead pacifist leaving 8 k's and 9 p's. at this point, the odds change a little against the p's and each successive 3 random meetings would raise the likelyhood of p's loosing their lives but even at this rate, the killers would surely be gone before the last pacifist meets one... in fact, i think the odds are that there would be about 3 or 4 pacifists left after all the killers are all gone.
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#8 nikimad

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Posted 11 October 2007 - 05:45 PM

you could have equal chances no matter what, just get a bus
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#9 bonanova

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Posted 12 October 2007 - 09:04 AM

Hint: the answer is different if there are 10 killers from the answer if there are 11 killers.
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#10 bonanova

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Posted 12 October 2007 - 09:32 AM

Kudos to writersblock [2nd post basically does it]

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




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