DS Topic Ratios - GMAT Tomorrow

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DS Topic Ratios - GMAT Tomorrow

by soni_pallavi » Thu Nov 22, 2012 11:55 pm
Q1

On a sightseeing tour the ratio of the number of women to children was 5 to 2.What was the number of men on the sightseeing tour?

1)On the sightseeing tour,the ratio of the number of children to the number of men was 5 to 11

2)The number of women on the sightseeing tour was less that 30

Ans c

Thanks

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by Anurag@Gurome » Sat Nov 24, 2012 4:11 am
soni_pallavi wrote:Q1

On a sightseeing tour the ratio of the number of women to children was 5 to 2.What was the number of men on the sightseeing tour?

1)On the sightseeing tour,the ratio of the number of children to the number of men was 5 to 11

2)The number of women on the sightseeing tour was less that 30

Ans c

Thanks
Say the number of men, women and children in the sightseeing tour are m, w and c respectively. Thus, w:c = 5:2 = (5/2) : 1

Statement 1: c:m = 5:11 = 1: (11/5)
Hence, m:w:c = (11/5) : (5/2) : 1 = 22:25:10
Thus, the possible numbers can be (22, 25, 10) or integer multiples of that like (44, 50, 20), (66, 75, 30) etc.

We don't know the total number or any other numbers, hence we cannot determine the number of men; NOT sufficient.

Statement 2: w < 30
We don't know anything about the number of men; NOT sufficient.

1 & 2 Together: As w is less than 30, only possible value of w is 25. Hence total number of men is 22; SUFFICIENT.

The correct answer is C.
Anurag Mairal, Ph.D., MBA
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