# Q. A student appeared in 6 papers. The maximum marks are the same for each paper. His marks in these papers are in the proportion 5 : 6 : 7 : 8 : 9 : 10. Overall he scored 60%. In how many number of papers did he score less than 60% of the maximum marks?

(a) 2

(b) 3

(c) 4

(d) 5

Correct Answer: (b) 3

#### Question from UPSC Prelims 2021 CSAT Paper

**Explanation : **

## Student’s Subject-wise Marks Analysis

Let total marks in each subject be 100. Therefore, total marks for all 6 subjects = 600. Overall marks scored = 60% of 600 = 360.

According to the question, 5x + 6x + 7x + 8x + 9x + 10x = 360 or 45x = 360; or x = 8.

So, marks in the given 6 subjects must be:

- 5 × 8 = 40
- 6 × 8 = 48
- 7 × 8 = 56
- 8 × 8 = 64

Hence, in 3 subjects, the student has scored less than 60% marks.