Q: A rectangle has length, width and diagonal as L, W and D resp. What is the length of the rectangle ?
1. L+W = 6
2. D^2 = 20 i.e D to the power of 2 = 20
Which choice would you mark (C) or (E). Thanks.
My assumption is the length of a rectangle is always the longest side.
Thanks
Ankush
Data Sufficiency Question - Easy but a challenging assumptio
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if D^2 = 20 => L^2 + W^2 = 20
Also, L+W = 6 => L^2 + W^2 + 2L*W = 36 i.e. L*W = 8
so, we have L* ( 6 - L) = 8 or L=2/4
now, the question says clearly that L is the length, so for me,
L = 4 is the correct answer.
What is the OA?
Also, L+W = 6 => L^2 + W^2 + 2L*W = 36 i.e. L*W = 8
so, we have L* ( 6 - L) = 8 or L=2/4
now, the question says clearly that L is the length, so for me,
L = 4 is the correct answer.
What is the OA?
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NEither 1 nor 2 alone are not suff
Combining:
we have
l+w=6, w=6-l
d^2=20
l^2 + (6-l)^2 = 20 solving we get
l^2 - 6l + 8 = 0
(l-2)(l-4)=0
l can be as 2 as 4, so I think answer wil be E until we are told that l>w.
I don't know whether lenght is always more than width in GMAT
Can anybody resolve my doubts?
I will choose E in this case
I think we need Stuart and Ian here!
Combining:
we have
l+w=6, w=6-l
d^2=20
l^2 + (6-l)^2 = 20 solving we get
l^2 - 6l + 8 = 0
(l-2)(l-4)=0
l can be as 2 as 4, so I think answer wil be E until we are told that l>w.
I don't know whether lenght is always more than width in GMAT
Can anybody resolve my doubts?
I will choose E in this case
I think we need Stuart and Ian here!
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answering to ten days ago
......the original question was what is the area of the rectangle ?
I just extended the question to calculating the length.
answering to 4meonly
How do we get Stuart or Ian here ?
......the original question was what is the area of the rectangle ?
I just extended the question to calculating the length.
answering to 4meonly
How do we get Stuart or Ian here ?
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The 'length' of a rectangle is normally equal to its longest side, so the answer here should be C, as I think has been explained adequately above. Still, the GMAT does *not* test whether you know obscure details about mathematical definitions. There is no chance that you would see a question exactly like this on the GMAT- if it were a real GMAT question, they would tell you that l > w. So don't worry about the minor technicality here that makes the answer C; if you found that 2 and 4 are the two side lengths, you've learned what you need to from the question.
For online GMAT math tutoring, or to buy my higher-level Quant books and problem sets, contact me at ianstewartgmat at gmail.com
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