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There are in all, 10 balls, some of them...

There are in all, 10 balls, some of them are red and the others white. The average cost of all balls is Rs 28. If the average cost of red balls is Rs 25 and that of white balls is Rs 30, the number of white balls is:

A

3

B

5

C

6

D

7

Text Solution

Verified by Experts

The correct Answer is:
C
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