For five classes A–E: total students, number in neither chess nor carrom, and chess:carrom ratio among the rest.

Class	Total	Neither	Chess:Carrom
A	420	119	4:3
B	330	88	7:4
C	240	110	8:5
D	125	45	2:3
E	390	130	8:5

What is the average of the number of students participating in carrom from D and chess from A?

A110 ✓ Correct

B130

C150

D125

Correct answer: (A) 110

Explanation

The answer is 110.

Carrom from D is 3 of 5 of 80, which is 48.

Chess from A is 4 of 7 of 301, which is 172.

The sum of these two is 48 plus 172, which is 220.

The average is 220 divided by 2.

That equals 110.

So the answer is 110.

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