GMAT Prep - Sight Seeing Tour

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by Nycgrl » Sun Jun 22, 2008 1:55 pm
Ans is C

We are given W/C = 5/2

1st Statment says C/M =5/11 - not suff
2 nd Number of women less tha 30 - not suff

Combine 1&2

If number of women is less than 30 then to get W/C =5/2 we get number of women as 25 and number of children as 10 (25/10 = 5/2)

we know number of children we can find out number of men using 1st statment.

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by rosh26 » Mon Jun 23, 2008 2:22 pm
Hmmm...but cant the number of women also be 15, and the number of children be 6 if the ratio is 5/2 ????

"Combine 1&2

If number of women is less than 30 then to get W/C =5/2 we get number of women as 25 and number of children as 10 (25/10 = 5/2) "

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by Nycgrl » Mon Jun 23, 2008 7:00 pm
Well for ratio of children to men be 5/11( statement one)the Number of children have to multiple of 5

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by ksh » Mon Jun 23, 2008 9:51 pm
Hi Nycgrl,

I am really not able to understand your logic to reach the answer. IMO we can proceed as follows:

Given w/c=5/2, where w=no. of women, c=no. of children

Stem1. c/m=5/11, using this and the premise we cant know no. of men in the group so, insuff

Stem2. No. of women is less than 30. this stem also doesnt allow us to get the no. of men in the group

Now, 1+2
w:c=5:2, c:m=5:11 and w=<30
w/c*c/m=5/2*5/11
or, w/m=25/22
if w is known, m can be found so, suff.

Hence C

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by AleksandrM » Tue Jun 24, 2008 9:31 am
From what I understand, for the ratio w:m:c to hold as 25:10:22, one of the numbers must be known. If there are less than 30 women, whe only way that the ratio can hold is if there are 25 women. If there are 27 women, for example, then the ratio will give you fractions for men and children. OR, if there are 50 women, then there are 20 children and 44 men.