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Author Topic: Brain Teaser  (Read 7210 times)

Offline ariel

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Brain Teaser
« on: 27/03/2006 00:15:20 »
OK, i found a website with brain teasers!
so i will post :D

NOBODY TRY GOOGLING[}:)]

ariel


 

Offline ariel

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Re: Brain Teaser
« Reply #1 on: 27/03/2006 00:16:24 »
The mystery of the missing fish
Two fathers and two sons went fishing. Each caught one fish. However, only three fishes were caught.
Q : How was this possible?

ariel
 

Offline Ophiolite

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Re: Brain Teaser
« Reply #2 on: 27/03/2006 00:26:53 »
That's simple. If you start by watching the clock you should be able to identify one of the fathers.

Observe; collate; conjecture; analyse; hypothesise; test; validate; theorise. Repeat until complete.
 

Offline upton

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Re: Brain Teaser
« Reply #3 on: 27/03/2006 00:37:39 »
son, father , grandfather ?

~~~I can't think of a signature~~~
 

Offline ariel

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Re: Brain Teaser
« Reply #4 on: 27/03/2006 01:22:52 »
correct upton!
:D

ariel
 

another_someone

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Re: Brain Teaser
« Reply #5 on: 27/03/2006 02:47:18 »
quote:
Originally posted by ariel

The mystery of the missing fish
Two fathers and two sons went fishing. Each caught one fish. However, only three fishes were caught.
Q : How was this possible?




You would have covered your options better if you had said there were only three catches, or to specify that no fish were thrown back.

You have allowed the possibility that some fishes were caught, thrown back, and caught again.



George
 

Offline ariel

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Re: Brain Teaser
« Reply #6 on: 27/03/2006 02:52:02 »
I didn't make it up...
I just got it from a website
:]
well here is another one!

A man was waiting at an airport for a plane to arrive. Suddenly, he heard someone call his name. Looking up, he saw an old friend of his hurrying toward him. "Hey, Bill!" called his friend. "How are you? I haven't seen you in years!" "How are you?" exclaimed Bill. "Wow, you look great!". "I am married now, to somebody you don't know," said the other. "This is my daughter." Bill smiled down at the little girl. "Hi, young lady. What's your name?" "It's the same as my mama's," said the girl. "Is that so," said Bill, winking at his friend. "Then your name must be Cindy!"
Q: How could he possibly know this?

ariel
 

another_someone

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Re: Brain Teaser
« Reply #7 on: 27/03/2006 05:53:00 »
quote:
Originally posted by ariel
A man was waiting at an airport for a plane to arrive. Suddenly, he heard someone call his name. Looking up, he saw an old friend of his hurrying toward him. "Hey, Bill!" called his friend. "How are you? I haven't seen you in years!" "How are you?" exclaimed Bill. "Wow, you look great!". "I am married now, to somebody you don't know," said the other. "This is my daughter." Bill smiled down at the little girl. "Hi, young lady. What's your name?" "It's the same as my mama's," said the girl. "Is that so," said Bill, winking at his friend. "Then your name must be Cindy!"
Q: How could he possibly know this?




Although, in practical terms, the more likely explanation is that he had just seen some document or label that contained her mother's name, that would be too trivial an answer for such a question.

The implied assumption (and most of these types of questions are really asking you to challenge implied assumptions) is that the woman Bill is married to is indeed the little girl's mother.  As I said, the standard practice in these questions is to challenge the default assumptions, and thus one is lead to the probability that the little girl's mother is not the current Mrs Bill, but someone who is indeed known to Bill's friend.



George
 

Offline ariel

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Re: Brain Teaser
« Reply #8 on: 27/03/2006 06:57:46 »
actually, Bill's friend is Cindy's mother
named Cindy as well
:]

ariel
 

Offline ariel

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Re: Brain Teaser
« Reply #9 on: 27/03/2006 06:58:51 »
here is another:

The strange sisters
It was the first day of school. The teacher had several children in her class. She asked all the new children to write down their names and their date of birth for her. The first two names she looked at were those of girls. She saw that they both had the same last name. They also had the same birthday - June 9,1973. "Will Jane and June Campbell please stand?" asked the teacher. Two girls stood up, and the teacher saw that they were just alike. "Oh, you're twins," she said. One of the girls shook her head. "No," she said. "We're sisters, but we're not twins."
Q: How could they be sisters and be the same age, but not twins?

ariel
 

another_someone

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Re: Brain Teaser
« Reply #10 on: 27/03/2006 07:14:38 »
quote:
Originally posted by ariel

here is another:

The strange sisters
It was the first day of school. The teacher had several children in her class. She asked all the new children to write down their names and their date of birth for her. The first two names she looked at were those of girls. She saw that they both had the same last name. They also had the same birthday - June 9,1973. "Will Jane and June Campbell please stand?" asked the teacher. Two girls stood up, and the teacher saw that they were just alike. "Oh, you're twins," she said. One of the girls shook her head. "No," she said. "We're sisters, but we're not twins."
Q: How could they be sisters and be the same age, but not twins?




It is possible to consider scenarios where they could be sisters, with an identical date of birth, but not twins, but none of the scenarios properly fit the rest of the question.

They could be half sisters (same father, different mother), and born on the same day, but why would they look so similar (some familial similarity, yes; but not “just alike”)?

The could be sisters in a convent, but that too does not fit the remaining facts, since we now not only need to answer why they look similar, but one would not expect children to already carry the title of sister.

I will have to think if there is a better answer to this.



George
 

another_someone

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Re: Brain Teaser
« Reply #11 on: 27/03/2006 07:17:53 »
quote:
Originally posted by ariel

actually, Bill's friend is Cindy's mother
named Cindy as well
:]




I'm sorry, I am not quite clear as to what you mean.  Are you saying that the friend was the little girl's mother, but did not know it; or are you saying the friend was the little girls grandmother?

In practice, the actual question could allow the friend to be almost anyone who knew that Bill had had a daughter by a girl called Cindy, who was not the current Mrs Bill – but I'm not sure which particular scenario you were suggesting was the actual answer.



George
 

Offline ariel

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Re: Brain Teaser
« Reply #12 on: 29/03/2006 01:29:15 »
yes, the friend was the little girl's mother...
but who said she did not know this?

ariel
 

Offline Carolyn

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Re: Brain Teaser
« Reply #13 on: 29/03/2006 02:45:36 »
are the sisters triplets,with a sister in another class?
« Last Edit: 29/03/2006 06:51:30 by Carolyn »
 

another_someone

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Re: Brain Teaser
« Reply #14 on: 29/03/2006 16:30:59 »
quote:
Originally posted by ariel

yes, the friend was the little girl's mother...
but who said she did not know this?




Bill said “this is my daughter”.  It seems under the circumstances particularly arrogant that he did not then say “this is our daughter”, but it would also seem superfluous to say this if the friend already knew herself to be the mother of the girl, and one must also assume that she would know the father to be Bill.

In fact, if the woman knew she had had a child by Bill, but Bill had introduced the girl as his daughter, one would expect her to jump to the conclusion that it was Bill's daughter by another woman.



George
 

Offline Carolyn

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Re: Brain Teaser
« Reply #15 on: 29/03/2006 17:19:04 »
quote:
Originally posted by another_someone

quote:
Originally posted by ariel

yes, the friend was the little girl's mother...
but who said she did not know this?


Bill said “this is my daughter”.  It seems under the circumstances particularly arrogant that he did not then say “this is our daughter”, but it would also seem superfluous to say this if the friend already knew herself to be the mother of the girl, and one must also assume that she would know the father to be Bill.

In fact, if the woman knew she had had a child by Bill, but Bill had introduced the girl as his daughter, one would expect her to jump to the conclusion that it was Bill's daughter by another woman.



George




Bill did not say this is my daughter.  His friend said it.
quote:
:
--------------------------------------------------------------------------------
Originally posted by ariel
A man was waiting at an airport for a plane to arrive. Suddenly, he heard someone call his name. Looking up, he saw an old friend of his hurrying toward him. His old friend was Cindy.

"Hey, Bill!" called his friend. "How are you? I haven't seen you in years!" "How are you?" exclaimed Bill.

His old friend, Cindy, said "Wow, you look great!". "I am married now, to somebody you don't know," said the other. "This is my daughter."

Bill smiled down at the little girl. "Hi, young lady. What's your name?" "It's the same as my mama's," said the girl. "Is that so," said Bill, winking at his friend. "Then your name must be Cindy!"
Q: How could he possibly know this?





« Last Edit: 29/03/2006 17:19:49 by Carolyn »
 

another_someone

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Re: Brain Teaser
« Reply #16 on: 29/03/2006 18:25:21 »
quote:
Originally posted by Carolyn

Bill did not say this is my daughter.  His friend said it.




Apologies – my foolishness.  That I read a change of voice at that point in the story is not unreasonable, but that I did not realise that it was an unsubstantiated assumption was an error on my part, and that when ariel suggested the friend was the mother (and hence female), while the question was posed about a male, should have highlighted the impossibility of the change of voice occurring at that point in the narrative (although my original response was a valid answer to what was known in the original narrative, but clearly the moment it becomes apparent that the friend is female, I should have realised that my answer no longer becomes sustainable).



George
 

Offline ariel

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Re: Brain Teaser
« Reply #17 on: 31/03/2006 02:47:07 »
quote:
Originally posted by Carolyn

are the sisters triplets,with a sister in another class?



that's correct:D

ariel
 

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Re: Brain Teaser
« Reply #17 on: 31/03/2006 02:47:07 »

 

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