Brain Teasers

Off-Topic conversations, forum games, fun topics and pretty much anything else that doesn't fit into any other forum.
sburnett21
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Brain Teasers

Postby sburnett21 » Thu Aug 08, 2013 10:39 am

It rained heavily on the 99th day, causing puddles to form. On the hundredth day, each prisoner looked in the puddle, saw their forehead, and asserted they were white.
Akito-Agito
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Brain Teasers

Postby Akito-Agito » Thu Aug 15, 2013 11:05 am

7 - you roll the persian rug
2 - they decided to wait 100 days and at the end of them to ask all to be freed , because they're bound to get it right if do it all at once.
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Tonex
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Brain Teasers

Postby Tonex » Thu Aug 15, 2013 6:18 pm

7 is correct. 2, no, they ask separately and will be killed if they are wrong. If that were the strategy, they would all ask day 1.
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Pwnage
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Brain Teasers

Postby Pwnage » Tue Aug 20, 2013 2:49 am

I would like to debate #9.

http://www.ebay.com/sch/i.html?_trksid=p2050601.m570.l1313.TR0.TRC0.XMoney&_nkw=Money&_sacat=0&_from=R40

You can easily buy money with money. So the real answer to this question is my satisfaction. Because no matter how much money or how many bullshit answers you give to it, anything can be purchased with money.
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Tonex
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Brain Teasers

Postby Tonex » Tue Aug 20, 2013 6:27 pm

When I say "buy money" I donot mean "scammed", nor am I referring to the rare commodities, as those are not money you can go the store and buy stuff with. Unless the store is an antique dealer.
Last edited by Tonex on Tue Aug 20, 2013 6:28 pm, edited 1 time in total.
trireaper
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Re: Brain Teasers

Postby trireaper » Sun Mar 16, 2014 2:33 am

2: They all assume that they have white painted on their foreheads, as everyone else is too. Either that, or they hope theirs is white and ask anyways.


Goin' grave digging!
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Tonex
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Re: Brain Teasers

Postby Tonex » Tue Mar 25, 2014 3:23 am

Sorry, that is also not the answer.
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Antiseen
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Re: Brain Teasers

Postby Antiseen » Wed Mar 26, 2014 3:10 am

2. (Paint would not last that long on your skin btw) They would all count the number of white foreheads they saw on the first day, if they saw 98 they would go on the 99th day, but if anyone went beforehand that would mean that only some of their heads were painted white as no man had gone on the 99th day meaning he had seen 99 painted foreheads that were white. So on the 100th day they realized that each man had to have a white painted forehead. That would mean that even if you could not see your own forehead that you could confirm through it lasting 100 days that you must have a white forehead.
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Re: Brain Teasers

Postby Insomnia » Wed Oct 29, 2014 1:39 am

Tonex wrote:2. There are 100 prisoners in a castle dungeon. One day, the warden gives a challenge to the prisoners.
They are told several things:
a. On the first day, each person's forehead will be painted either black or white.
b. At the end of each day, a prisoner may assert whether his forehead is painted white. If their forehead is painted white, the prisoner will go free. However, if their forehead is painted black, the prisoner will be executed.
c. If all of the prisoners with white foreheads are freed, the remaining prisoners will be freed as well.
d. If the prisoners communicate whatsoever, other than determining the color of the other foreheads, or all of the prisoners will be executed.
e. At least one forehead will be painted white.
The warden then allowed all of the prisoners to discuss a strategy for trying to free themselves, then painted all of the prisoner's foreheads white. After 100 days of doing nothing, every single prisoner asked to be freed. What was their strategy?


I want an answer
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Tonex
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Re: Brain Teasers

Postby Tonex » Thu Oct 30, 2014 9:06 pm

Antiseen is incorrect, I'll post the answer when I'm not on my phone.
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Tonex
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Re: Brain Teasers

Postby Tonex » Mon Nov 03, 2014 1:55 am

Here's the solution. The original problem there was essentially the same, but with different words.
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Pwnage
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Re: Brain Teasers

Postby Pwnage » Mon Nov 03, 2014 11:53 pm

I remember one of my math professors giving us that problem once, and I was extremely satisfied with the solution.
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Tonex
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Re: Brain Teasers

Postby Tonex » Tue Nov 04, 2014 7:56 am

The more difficult question is, what new information did the person give by saying that there is at least one person with a blue forehead?
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Jesse James
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Re: Brain Teasers

Postby Jesse James » Wed Nov 05, 2014 8:18 pm

tl;dw :|