The riddle thread

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Liudeius

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Avistew said:
okay, then
she only talks once, saying there is one person with blue eyes. If there was only one overall, that person would know right away. They don't, so if there were 2 the next day they would both know, and so on.
That means on the 100th day, all people with blue eyes know they have blue eyes, and they all leave, but all the brown eyed people stay.
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SckizoBoy

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A Hermit's Cave
Liudeius said:
Edit:
Still no, She only says the one sentence one time.

The brown eyed people never leave.
However:

As they see other people with brown eyes, they can necessarily substitute the idea of 'blue eyes' with 'brown eyes'. However, they need everyone with blue eyes to leave since they are as yet unaware of the potential presence of a third eye colour, the Guru aside.

Therefore, on the morning of the 101st day, everyone reappears, only 100 brown eyed people with individuals only seeing brown eyes but unaware of their own. Thus, they can think to themselves 'the Guru has effectively told us that she observes at least one person with brown eyes, because I observe no other colour'. Same principle as per 'blue eyes' deduction, then, one hundred days later...

*shrug* perhaps?
 

Liudeius

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SckizoBoy said:
Liudeius said:
Edit:
Still no, She only says the one sentence one time.

The brown eyed people never leave.
However:

As they see other people with brown eyes, they can necessarily substitute the idea of 'blue eyes' with 'brown eyes'. However, they need everyone with blue eyes to leave since they are as yet unaware of the potential presence of a third eye colour, the Guru aside.

Therefore, on the morning of the 101st day, everyone reappears, only 100 brown eyed people with individuals only seeing brown eyes but unaware of their own. Thus, they can think to themselves 'the Guru has effectively told us that she observes at least one person with brown eyes, because I observe no other colour'. Same principle as per 'blue eyes' deduction, then, one hundred days later...

*shrug* perhaps?
It's kind of hard to think for 100 people, but still I'm quite sure, no.

It only works because the seed of "one person with blue eyes" was planted, so each consecutive day they know that there must be another person with blue eyes.
Without being told that there is at least one person with brown eyes, the reasoning that the blue eyed people used to get off the island can't be communicated.
The official answer is the blue eye people in 100 days. I too have tried to think around this answer, but I just leave it as is when telling people the solution.
Here is XKCD's solution by the way [link]http://xkcd.com/solution.html[/link].
 

Mortier

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Hmm I remember a certain Sphinx object in Heroes of Might and Magic 3, it had TONS and TONS of riddles, better post a few:

"When one does not know what it is,
then it is something;
but when one knows what it is,
then it is nothing.
What is it?"

"What is neither inside the house,
nor outside the house,
but lets you see both?"

"There was a green round house.
Inside the green round house was a smaller white house.
In the white house was a red house.
And living in the red house were lots of little black babies."

Should be enough to start myself off for now :)
 

SckizoBoy

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Liudeius said:
It's kind of hard to think for 100 people, but still I'm quite sure, no.

It only works because the seed of "one person with blue eyes" was planted, so each consecutive day they know that there must be another person with blue eyes.
Without being told that there is at least one person with brown eyes, the reasoning that the blue eyed people used to get off the island can't be communicated.
The official answer is the blue eye people in 100 days. I too have tried to think around this answer, but I just leave it as is when telling people the solution.
Here is XKCD's solution by the way [link]http://xkcd.com/solution.html[/link].
I guess so... 'there is no more potent a virus as an idea', though my answer was based on the below being literal.

Liudeius said:
They are all perfect logicians -- if a conclusion can be logically deduced, they will do it instantly.
That there are only two observed colours... therefore, day 101: there are no blue-eyed people left upon this island, hence there are but those with brown eyes, and myself etc. In any case, the reasoning to get off the island wasn't discretely communicated, only inferred and logic thusly provided the reasoning to get off the island. It's just one extra level of (re)interpretation of that statement to get the brown eyed lot off. Probably the best way to remove any ambiguity in the riddle is to have three colours (Guru aside).

Still - philosophical: define logic. Question - is it so influenced by suggestion?

I think that is a discussion best kept for later...
 

DasDestroyer

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paynexkiller said:
^ The one about moving some where, where he can see the bear? Is it the outskirts of Russia?

Also, How Is a Raven like a writing desk?
o_O
This is one of the random things I was thinking about when trying to go to sleep yesterday...
Anyway, that answer is Poe wrote on both.
 

Jordi

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SckizoBoy said:
Liudeius said:
Edit:
Still no, She only says the one sentence one time.

The brown eyed people never leave.
However:

As they see other people with brown eyes, they can necessarily substitute the idea of 'blue eyes' with 'brown eyes'. However, they need everyone with blue eyes to leave since they are as yet unaware of the potential presence of a third eye colour, the Guru aside.

Therefore, on the morning of the 101st day, everyone reappears, only 100 brown eyed people with individuals only seeing brown eyes but unaware of their own. Thus, they can think to themselves 'the Guru has effectively told us that she observes at least one person with brown eyes, because I observe no other colour'. Same principle as per 'blue eyes' deduction, then, one hundred days later...

*shrug* perhaps?
The explanation for the blue eyed people starts with the idea that if there is only 1 blue eyed person, he can leave on the first day. If there are 2 blue-eyed people and the other person didn't leave on day 1, they both know they have blue eyes. It builds on the idea that the rest is rational as well.

But for the brown-eyed people, who very well know that there is at least 1 brown-eyed person (because they see 99), this doesn't work. Again, imagine if there was only 1. For one thing, he doesn't know that there is at least 1 brown-eyed person, because he can't see anyone else (since he's alone), so all he knows is that he has no blue eyes (after all of those people left).
If there were two people left, they can see there is at least one brown-eyed person, but now they can't assume that the other person would leave after 1 day if he is the only one with brown eyes.
 

Avistew

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Mortier said:
"What is neither inside the house,
nor outside the house,
but lets you see both?"
a window?

Mortier said:
"There was a green round house.
Inside the green round house was a smaller white house.
In the white house was a red house.
And living in the red house were lots of little black babies."
I'm assuming a fruit of some sort... Some fruit have shells, then the skin, then the flesh, and then there would be the seeds. But I can't think of a fruit that matches right now.
 

Mortier

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Avistew said:
Mortier said:
"What is neither inside the house,
nor outside the house,
but lets you see both?"
a window?

Mortier said:
"There was a green round house.
Inside the green round house was a smaller white house.
In the white house was a red house.
And living in the red house were lots of little black babies."
I'm assuming a fruit of some sort... Some fruit have shells, then the skin, then the flesh, and then there would be the seeds. But I can't think of a fruit that matches right now.
Say, you're good :p
Anyway, ur almost there with the second one yeah. Nothing on the first one? :(
 

DasDestroyer

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Mortier said:
Hmm I remember a certain Sphinx object in Heroes of Might and Magic 3, it had TONS and TONS of riddles, better post a few:

"When one does not know what it is,
then it is something;
but when one knows what it is,
then it is nothing.
What is it?"

"What is neither inside the house,
nor outside the house,
but lets you see both?"

"There was a green round house.
Inside the green round house was a smaller white house.
In the white house was a red house.
And living in the red house were lots of little black babies."

Should be enough to start myself off for now :)
Secret, window, watermelon
 

Avistew

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Mortier said:
Say, you're good :p
Anyway, ur almost there with the second one yeah. Nothing on the first one? :(
Thanks :D I like trying to figure out the "trick" and how you're supposed to think for these kind of little riddles.

About the first one, I don't really know.

I was thinking something like doubt or uncertainty, but I'm trying to find what fits perfectly with the "something"/"nothing" thing.

And I think I figured out the third one
a watermelon?
 

Mortier

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DasDestroyer said:
Secret, window, watermelon
Avistew said:
Thanks :D I like trying to figure out the "trick" and how you're supposed to think for these kind of little riddles.

About the first one, I don't really know.

I was thinking something like doubt or uncertainty, but I'm trying to find what fits perfectly with the "something"/"nothing" thing.

And I think I figured out the third one
a watermelon?
Ur both right on the second and third one now ^^
Keep trying for the first one, though :p (Das is close, in a way.)

In the mean time, I could post more riddles if you want to.
 

DasDestroyer

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Obligatory Monty Hall problem:
Imagine that the set of Monty Hall's game show Let's Make a Deal has three closed doors. Behind one of these doors is a car; behind the other two are goats. The contestant does not know where the car is, but Monty Hall does.

The contestant picks a door and Monty opens one of the remaining doors, one he knows doesn't hide the car. The contestant is then offered to change her pick.

Should the contestant do so?
Also:
A king summons his 4 wise men to find out which one is the wisest. He has them stand one after the other, all looking forward, and he puts a cap onto each one of them, a blue one on the first wise man, a red one on the second wise man, another blue cap on the third one and a red cap on the last wise man. Each man can only see the caps of the wise men in front of him. The king tells them that there are two blue and two red caps, and that the first two men to figure out the color of their caps are free to leave, the remaining two will be exiled. The wise man who was standing last was the first to leave. Which one of the 3 remaining men will leave?
Sorry if the latter is written crappily, I haven't had any sleep so as to prevent jet lag after my upcoming flight :)
 

Shoqiyqa

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paynexkiller said:
TheDarkEricDraven said:
paynexkiller said:
How Is a Raven like a writing desk?
Because there is a B in both and an N in neither.
I think the original writer of Alice, said that it couldn't be solved. But then I've heard people have their own answers. So... Yes? I think? Lol.
http://twolumps.keenspot.com/d/20081107.html

DasDestroyer said:
Obligatory Monty Hall problem:
Imagine that the set of Monty Hall's game show Let's Make a Deal has three closed doors. Behind one of these doors is a car; behind the other two are goats. The contestant does not know where the car is, but Monty Hall does.

The contestant picks a door and Monty opens one of the remaining doors, one he knows doesn't hide the car. The contestant is then offered to change her pick.

Should the contestant do so?
http://www.escapistmagazine.com/forums/read/18.199542-Poll-Lets-make-a-Deal-Statistics-and-math-question-Most-people-get-this-wrong?page=1

 

Avistew

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DasDestroyer said:
Obligatory Monty Hall problem
I know it's been answered, but I had this answer before reading the post so I'm posting it anyways.
At the time you picked a door, you had one chance in three to be right. But because no matter what door you choose, the guy eliminates one wrong possibility, there is a chance in two that the other door has the prize, while only a chance in three that the door you originally picked has it. Therefore the probability is higher that the prize is under the other door, and you should switch.
Explained a different way: it's only a bad idea to switch if the door you picked at the beginning was the right one. Since there is only one in three chances of that, that means two times out of three changing your pick is better.

DasDestroyer said:
Wise men problem
Does the guy in the back, the one who guessed what colour his hat was (easily, since he could see the other three) tell everyone else? I'm assuming no, but if yes, the answer is that the third person would get the right answer.
However, if he does NOT, then the second person gets the colour right. The second person thinks "if both my hat and the hat of the guy right in front of me were the same colour, the third guy would have known what colour his hat was. Since he doesn't, my hat isn't the same colour as the guy in front of me", and therefore guesses his hat colour.