A basic quant question

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Source: — Data Sufficiency |

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by gmatguy16 » Sun Jan 06, 2008 10:57 am
it could mean either way

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by sankruth » Sun Jan 06, 2008 12:00 pm
I too thought the same but came across a DS problem in GMAT Quant Review book where the official solution uses A - B.

In this problem if interpret st#2 as B - A the answer will be different...

The perimeter of a rectangular garden is 360 feet. What is the length of the garden?

1. The length of the garden is twice the width

2. The difference between length and width of the garden is 60 feet.

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by Tud » Sun Jan 06, 2008 12:27 pm
That's interesting. Statement 1 is sufficient, but statement 2 will depend on how you interpret "difference". The official answer would tell us how they interpret it, so....., what's the OA?

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by sankruth » Sun Jan 06, 2008 1:00 pm
The OA is D

St 2 is intrpreted as (l - w) only!

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by Tud » Sun Jan 06, 2008 3:26 pm
sankruth wrote:The OA is D

St 2 is intrpreted as (l - w) only!
That's good to know, so we can assume that when they say the difference of a and b they mean a-b only.

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by Argen » Mon Jan 07, 2008 9:09 am
I think by definition, the length of a rectangle is the longer side and the width shorter side.

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by II » Mon Jan 07, 2008 9:25 am
Argen wrote:I think by definition, the length of a rectangle is the longer side and the width shorter side.
Good point !

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by sankruth » Mon Jan 07, 2008 11:53 am
Thanks! That makes it very clear!

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by camitava » Mon Jan 07, 2008 10:56 pm
Guys a long discussion it was! But I am not getting one point and also I would like to express my view -
Guys this is a Qs from DS. Our aim should be to find out whether the ways the options are mentioning can take us to the conclusion. Now going back to ur Qs sankruth -
The perimeter of a rectangular garden is 360 feet. What is the length of the garden?

1. The length of the garden is twice the width

2. The difference between length and width of the garden is 60 feet.
If we go with 1, we can get the value of l and w.
Again if we go with 2, l - w =60
2(l + w) = 360 or l + w = 180 - By these two equ, we can get the value of l and w.
If you take option - 2 as w - l = 60 then also u can get the value of w and l.
It can happen that the values we are getting may not match with the answer directed by other option.
But bottom-line is we can get the value of length by the two options specified. So D is fine!
I am not getting where I missed! Please let me know if I am wrong anyhow.
Correct me If I am wrong


Regards,

Amitava

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by sankruth » Tue Jan 08, 2008 1:46 am
camitava,
Length is always the longer dimension and this is as defined in the dictionary. This assumption is key to interpreting st#2

Anyway, if one goes with the interpretion of st#2 as (w - l), then one must also consider the interpretation, (l - w). Each interpretaion will give a different value for l, thus making st#2 INSUFF.

Hope that helps!