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

Monjur Alahi

In a class of 100 students, there are 70 boys whose average marks in a subject is 75. If the average marks of the complete class is 72, then what is the average of the girls ?
A. 73
B. 65
C. 68
D. 74


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Salim Ahmed Kawsar

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Correct Answer - 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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