Building

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Building

by acorra » Sun Nov 09, 2008 9:57 am
Alan and Betty live in a multi-story apartment building. How many stories does the building have?

1) There are 3 stories between those on which Alan and Betty live

2) There are 9 stories above Alan's floor and 9 stories below Betty's floor


Many thanks
Andrew
Source: — Data Sufficiency |

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by cramya » Sun Nov 09, 2008 10:23 am
E) oa please?

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by acorra » Sun Nov 09, 2008 10:24 am
wrong!

OA is E

cheers
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by stop@800 » Sun Nov 09, 2008 10:42 am
IMO E


try n solve it with number line


A
---------A-----3--------S--------
cant tell before A and after S
so insuff


B
above A 9 and below B 9
here we dont know the difference so Insuff


A+B
it looks C is the answer but there is a catch
we dont know A/S who lives on higher floor
consider two drms

----6----A-----3--------S---6----

----9----S-----3--------A---9----

hence Insuff

Hope this helps

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by logitech » Sun Nov 09, 2008 10:43 am
stop@800 wrote:IMO E


try n solve it with number line


A
---------A-----3--------S--------
cant tell before A and after S
so insuff


B
above A 9 and below B 9
here we dont know the difference so Insuff


A+B
it looks C is the answer but there is a catch
we dont know A/S who lives on higher floor
consider two drms

----6----A-----3--------S---6----

----9----S-----3--------A---9----

hence Insuff

Hope this helps
Somebody studied his OG book! :lol:
LGTCH
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"DON'T LET ANYONE STEAL YOUR DREAM!"

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by cramya » Sun Nov 09, 2008 11:14 am
it looks C is the answer but there is a catch
we dont know A/S who lives on higher floor
consider two drms

----6----A-----3--------S---6----

----9----S-----3--------A---9----

hence Insuff

Hope this helps
Stop@800,

The diagram above; will it not contradict the fact that there are 9 stories above Alan's floor and 9 stories below Betty's floor

Should it not be

6---- B(S whatever))----3----A------6 which will be 15

9-----A------3-------B(S whatever)---------9 which will be 21

Hence E)

Hope I am not missing something here; feell free to jump in bud

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by stop@800 » Sun Nov 09, 2008 11:42 am
cramya wrote:
it looks C is the answer but there is a catch
we dont know A/S who lives on higher floor
consider two drms

----6----A-----3--------S---6----

----9----S-----3--------A---9----

hence Insuff

Hope this helps
Stop@800,

The diagram above; will it not contradict the fact that there are 9 stories above Alan's floor and 9 stories below Betty's floor

Should it not be

6---- B(S whatever))----3----A------6 which will be 15

9-----A------3-------B(S whatever)---------9 which will be 21
I am sorry, But I could not find the point of error.

I think we both have drawn similar diagram.

Hence E)

Hope I am not missing something here; feell free to jump in bud

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by cramya » Sun Nov 09, 2008 12:19 pm
I am sorry, But I could not find the point of error.

I think we both have drawn similar diagram.
Never mind ; I was trying to saythat your A and S are interchanged ; the diagram is correct as far as the numbers go... Its no big deal since the concept underlying is the same....

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Re: Building

by logitech » Sun Nov 09, 2008 12:40 pm
acorra wrote:Alan and Betty live in a multi-story apartment building. How many stories does the building have?

1) There are 3 stories between those on which Alan and Betty live

2) There are 9 stories above Alan's floor and 9 stories below Betty's floor


Many thanks
Andrew
Andrew, think this problem as an ABSOLUTE value problem/

statement 1 means ABS (A-B) = 3

So start thinking about the OPTION E, before you start your solution.
LGTCH
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