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DanMushMan
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#41
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#41
(Original post by 4Ed)
what would THE OTHER guy say if u asked him which way to go
that's right
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elpaw
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#42
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#42
(Original post by _EMMA_)
Five hundred begins it, five hundred ends it,
Five in the middle is seen;
First of all figures, the first of all letters,
Take up their stations between.
Join all together, and then you will bring
Before you the name of an eminent king.

who?
DAVID
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GH
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#43
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#43
(Original post by elpaw)
"are the answers to 'Are you fishpaste?' and 'this is the door to heaven?' (pointing at a door) both yes?"

yes: it is the door to heaven
no: it is the door to hell

(you get the same result from both of them)
you can only ask 1 question
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_EMMA_
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#44
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#44
(Original post by fishpaste)
Four people are being held hostage. They are standing as follows:

^ | _ ^ _
O | O O O

That's a wall in between them, so the guy on the left can't see the other guys, and vice versa. The things on top are hats. They are all facing towards the wall, and can't turn around and look behind them. They can't tell what kind of hat they're wearing, and they can only see the hats of the people in front of them. So for example, the guy on the far right can see that there are two people in front of him, one wearing a flat hat and one wearing a pointy. The middle guy can only see the guy in front of him wearing a flat hat. THey can't speak either.

The people holding them hostage agree to let them go if one can figure out which kind of hat they're wearing, if they're wrong, they're all shot, so it's inadviseable to guess. They're also told that there are two flat hats, and two pointy hats. Who figures out what kind of hat they're wearing? How?
how can there be a guy in the middle if the number is even?
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elpaw
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#45
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#45
(Original post by 2776)
you can only ask 1 question
it is only one question
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fishpaste
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#46
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#46
(Original post by _EMMA_)
how can there be a guy in the middle if the number is even?
Sorry, assumption, I meant in the middle of the three on the right.
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_EMMA_
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#47
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#47
(Original post by fishpaste)
Sorry, assumption, I meant in the middle of the three on the right.
maybe the guy on the far right because he can see two, with different hats and knows what he is wearing himself

am I right?
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fishpaste
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#48
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#48
(Original post by _EMMA_)
maybe the guy on the far right because he can see two, with different hats and knows what he is wearing himself
The guy on the right can see a flat hat and a pointy hat, that means there is still a flat hat and a pointy hat unaccounted for, he could be wearing either. He only has a 50/50 chance of getting it right. There's a way of knowing 100%.
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4Ed
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#49
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#49
here's one:

there are 2 rooms, one with 3 light switches, and one with 3 light bulbs. each switch is connected to one bulb, but u dont no which. by entering each room only once, how do u find out which switch connects to which bulb? (it is mathematically provable that this prob cannot be solved )
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elpaw
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#50
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#50
the guy on the end would know if the 2 in front had the same type, but they dont. the guy in the middle can see the one in front, and because the back guy hasn't spoken, he knows that he is wearing a pointy. so he says this, and they are released.
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elpaw
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#51
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#51
(Original post by 4Ed)
(it is mathematically provable that this prob cannot be solved )
so why are you asking it?
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fishpaste
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#52
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#52
(Original post by elpaw)
the guy on the end would know if the 2 in front had the same type, but they dont. the guy in the middle can see the one in front, and because the back guy hasn't spoken, he knows that he is wearing a pointy. so he says this, and they are released.
Excellent, perfect answer. Seen it before? Or deduced it yourself? If so, you're awfully bright.
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elpaw
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#53
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#53
(Original post by fishpaste)
Excellent, perfect answer. Seen it before? Or deduced it yourself? If so, you're awfully bright.
i did it myself, but i knew of the types where you wait for an answer from someone who knows more than you and if it doesn't come you can make assumptions about what the situation is.

of course you have to assume that they think at a quick pace, otherwise the guy at the end could be really slow and still counting the number of hats or something when the middle guy shouts out the wrong answer.
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fishpaste
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#54
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#54
(Original post by elpaw)
i did it myself, but i knew of the types where you wait for an answer from someone who knows more than you and if it doesn't come you can make assumptions about what the situation is.
I see. Got any more examples of these? This is the only type I've seen.
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4Ed
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#55
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#55
(Original post by elpaw)
so why are you asking it?
cuz u can solve it thats why (it goes to show that maths does not always produce the right answer)
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elpaw
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#56
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#56
(Original post by 4Ed)
cuz u can solve it thats why (it goes to show that maths does not always produce the right answer)
are you saying it does have an answer? even though mathematically it doesnt?

EDIT: yeah i can see an answer now, you just follow the wiring!
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tommypip
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#57
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#57
(Original post by 4Ed)
here's one:

there are 2 rooms, one with 3 light switches, and one with 3 light bulbs. each switch is connected to one bulb, but u dont no which. by entering each room only once, how do u find out which switch connects to which bulb? (it is mathematically provable that this prob cannot be solved )

You turn on switch one and leave it on for 10 mins, turn it off and turn on switch two then go and look at the bulbs. The bulb that is off but hot is switch one, the bulb that is on is switch 2 and the bulb that is off and cold is switch 3
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4Ed
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#58
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#58
does anyone want to have a guess at how to do this? I was quite chuffed cuz i worked this out myself before the answer came out (this was posed in some lecture)

mathematically speaking, since u can only go into each room once, u only have 4 options: turning them all on, turning one on, turning two on and not turning any on. at best, it seems that u can only discover 1 light-switch combo.

yeah I wanna ask about this prisoner's dilemma as well..... if they aren't allowed to communicate, then how do they choose who answers this? they cant all possibly think along the same line
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elpaw
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#59
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#59
(Original post by tommypip)
You turn on switch one and leave it on for 10 mins, turn it off and turn on switch two then go and look at the bulbs. The bulb that is off but hot is switch one, the bulb that is on is switch 2 and the bulb that is off and cold is switch 3
what if the bulbs are energy-saving?
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tommypip
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#60
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#60
(Original post by 4Ed)
does anyone want to have a guess at how to do this? I was quite chuffed cuz i worked this out myself before the answer came out (this was posed in some lecture)

mathematically speaking, since u can only go into each room once, u only have 4 options: turning them all on, turning one on, turning two on and not turning any on. at best, it seems that u can only discover 1 light-switch combo.

yeah I wanna ask about this prisoner's dilemma as well..... if they aren't allowed to communicate, then how do they choose who answers this? they cant all possibly think along the same line

I'm sure my answer is right. Didn't David Blaine pose this while he was in the box? Do I get rep for getting it right?
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