# CAT Practice : Percents, Profits

Number of Students

## Total Number of Students

Q.21: In a practice paper at 2iim.com, questions were given from 5 topics. Out of the appearing students, 10% passed in all topics while 10% did not pass in any. Of the remaining, 20% passed in one topic only and 25% in two topics only. If 24% of the total students passed 4 topics only and 500 students passed in 3 topics only, find the total number of students who appeared in the examination?
1. 2500
2. 2000
3. 1600
4. 4545

Choice A. 2500

## Detailed Solution

Let the number of appearing students be 100.

Pass only in 0 topic – 10

1 – 16 (20% of 80)

2 – 20 (25% of 80)

3 – 20% (100 – (16+20+24+20))

4 – 24%

5 – 20%

Therefore, 20% of x = 500 = ) x = 2500

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