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  #1  
Old 11-02-2005, 06:43 PM
lotus776 lotus776 is offline
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Default math teaser, kinda tough

The crew of a certain train consists of a brakeman, a conductor, an engineer, and a fireman, named in one order or another Art, John, Pete, and Tom.

John is older than Art
The brakeman has no relatives on the crew
The engineer and the fireman are brothers
John is Pete's nephew
The fireman is not the conductor's uncle, and the conductor is not the engineer's uncle.

which position does each man hold, and how are the men related?

good luck
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  #2  
Old 11-02-2005, 07:00 PM
Trantor Trantor is offline
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Default Re: math teaser, kinda tough

[ QUOTE ]
The crew of a certain train consists of a brakeman, a conductor, an engineer, and a fireman, named in one order or another Art, John, Pete, and Tom.

John is older than Art
The brakeman has no relatives on the crew
The engineer and the fireman are brothers
John is Pete's nephew
The fireman is not the conductor's uncle, and the conductor is not the engineer's uncle.

which position does each man hold, and how are the men related?

good luck

[/ QUOTE ]

Here goes;

Art brakeman, John conductor, Pete engineer, Tom fireman.
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  #3  
Old 11-02-2005, 07:04 PM
AleoMagus AleoMagus is offline
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Default Re: math teaser, kinda tough

Brakeman is Art
Conductor is John
Engineer is Pete
Fireman is Tom

Art is unrelated
John is Pete's nephew and Tom's son
Pete is Tom's brother and John's uncle
Tom is Pete's brother and John's father

I think this satisfies all the conditions, but I am unsure why it matters that John is older than Art, Perhaps this means I am wrong

Regards
Brad S
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  #4  
Old 11-02-2005, 07:12 PM
lotus776 lotus776 is offline
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Default Re: math teaser, kinda tough

excellent work
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  #5  
Old 11-02-2005, 07:33 PM
Trantor Trantor is offline
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Default Re: math teaser, kinda tough

[ QUOTE ]
Brakeman is Art
Conductor is John
Engineer is Pete
Fireman is Tom

Art is unrelated
John is Pete's nephew and Tom's son
Pete is Tom's brother and John's uncle
Tom is Pete's brother and John's father

I think this satisfies all the conditions, but I am unsure why it matters that John is older than Art, Perhaps this means I am wrong

Regards
Brad S

[/ QUOTE ]

How did you get to Tom is the fireman without knowing John is older than Art? I got to conductor John is the nephew of the engineer (Pete) and the son of the fireman.

This left Art and Tom as one or other of the brakeman and fireman. John is younger than his dad and we know the engineer is Pete . The only other youger person available is the non-relative brakeman who must be Art, and so the fireman is Tom.
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  #6  
Old 11-03-2005, 06:46 AM
Siegmund Siegmund is offline
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Default Re: math teaser, kinda tough

[ QUOTE ]

How did you get to Tom is the fireman without knowing John is older than Art? I got to conductor John is the nephew of the engineer (Pete) and the son of the fireman.


[/ QUOTE ]

If Person A is Person B's brother, and Person C is Person B's nephew, that does NOT imply that Person C is Person A's child. A brother of a father must be an uncle, but a brother of an uncle might be a father, another uncle, or someone unrelated by blood at all.

And it is, of course, possible for nephews to be older than uncles.

Not saying your solution is wrong - it may still be the only one logically consistent - just that it's not obvious to me how/why you leap to the conclusion that there's a father and son in the mix.
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  #7  
Old 11-03-2005, 01:10 PM
setzf setzf is offline
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Default Re: math teaser, kinda tough

Art is the brakeman not related to anyone
pete is the engineer, toms brother and johns uncle
john is conductor, toms nephew, petes nephew
tom is the fireman, petes brother and johns uncle

that was fun
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  #8  
Old 11-03-2005, 01:20 PM
setzf setzf is offline
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Default Re: math teaser, kinda tough

i just realised something...i dont think this question is well formulated and i think the only way to solve it is to add an assumption, ie:
Age(John)>Age(Art) does not imply Art is not John's uncle (in reality) since uncles CAN be younger than nephews.
So to solve the problem i think (but am not sure) that you MUST assume that uncles cannot be younger than nephews

thoughts?
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  #9  
Old 11-03-2005, 01:22 PM
AleoMagus AleoMagus is offline
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Default Re: math teaser, kinda tough

The fireman is not the conductor's uncle. Yet you have:

[ QUOTE ]
john is conductor, toms nephew, petes nephew


[/ QUOTE ]

and since you also say that tom is the fireman, this makes this relationship between the two impossible. As Pete and Tom are brothers, this means that Tom must actually be John's Father.

Regards
Brad S
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  #10  
Old 11-03-2005, 01:25 PM
AleoMagus AleoMagus is offline
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Default Re: math teaser, kinda tough

You are correct. I did need to know that John was older than Art. As for my impression that you didn't need to know, I now realize that I was wrong.

I managed to narrow it down to John being the conductor and Pete being the engineer. Then I knew it had to be one of the two options of Art/tom as Engineer/brakeman. I simply tried the first and tested it for consistency against all the assumptions. It worked and I rushed to post, only realizing a couple of minutes later why the second option was impossible. For this, you need the relative ages of John and Art.

So in a sense, I got a little lucky that I tried the correct option first, though it did indicate the incompleteness of my method.

Regards
Brad S
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