GMAT prep 1

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GMAT prep 1

by saurabhmahajan » Sun Sep 05, 2010 3:44 am
How can we derive the number of women correctly when its just mentioned as a range ?

here in this case it is less than 30 (so it can be 25....15....18 anything )
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Saurabh Mahajan

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by selango » Sun Sep 05, 2010 5:08 am
W:C=5:2

stmt1,

C:M=5:11

W:C:M=25:10:22


No info abt number of men.

Insuff

stmt2,

w<30

No info abt number of men

In suff

Combining 1 and 2,

W<30

W:C:M=25:10:22 or 25x:10x:22x

where x is an integer

w<30 means only value of W is 25 and x is 1

M=22

Suff

Pick C
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by sdotcruz » Wed Sep 08, 2010 5:03 am
saurabhmahajan,

If you set the number of women to any number other than 25 the ratio will give you fractions of people. For instance set the number of women to 15. Then there are 6 children (2*3) and there will be 13.2 men (11 *1.2). The one point two was the multiple required to set the number of children from 5 to 6. 25 is the only number of women that works with the ratios.


The question is tricky and with some DS you need to manipulate information before you can decide if either answer is sufficient.

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by Gurpinder » Wed Sep 08, 2010 7:22 am
@selango

Hey,

I got up to the point of: C:W:M = 10:25:22

But can you explain how Stmt 2 helps with this ratio?

Thanks,
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by selango » Wed Sep 08, 2010 8:26 am
Gurpinder wrote:@selango

Hey,

I got up to the point of: C:W:M = 10:25:22

But can you explain how Stmt 2 helps with this ratio?

Thanks,
Ok now the ratio is 10:25:22

-->C:W:M = 10x:25x:22x

Note that Number of women is a multiple of 25.

Number of Women<30

Only value which is less than 30 and multiple of 25 is 25.

Number of women=25-->x=1

Number of men=22

Hope this clarify!!!!
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by Gurpinder » Wed Sep 08, 2010 9:09 am
selango wrote:
Gurpinder wrote:@selango

Hey,

I got up to the point of: C:W:M = 10:25:22

But can you explain how Stmt 2 helps with this ratio?

Thanks,
Ok now the ratio is 10:25:22

-->C:W:M = 10x:25x:22x

Note that Number of women is a multiple of 25.

Number of Women<30

Only value which is less than 30 and multiple of 25 is 25.

Number of women=25-->x=1

Number of men=22

Hope this clarify!!!!
omg..

that was simple. thanks!!!
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by lokesh r » Wed Sep 08, 2010 12:12 pm
A.

Ratio c:w:m = 10:25:22

Insufficient need not have to comment.

B. No of women<30
Nothing can be decided about no of men in group

A & B

Say total no of members in group is x

No of women 25/57* x < 30

Multiple values of x satifies above solution. So naturally no of men 22/57*x does varies.

So C also is not sufficient.