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In a class of 100 students there are 70 ...

In a class of 100 students there are 70 boys whose average marks in subject are 75. If the average marks of the complete class are 72, then the average marks of the girls

A

73

B

65

C

68

D

74

Text Solution

Verified by Experts

The correct Answer is:
B
Total students =100
Total marks of 70 students is `75xx70=5250`.
Total marks of girls is 7200-5250=1950
So average of girls is
`(1950)/(30)=65`
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