Question

The average of marks scored by the students of a class is $68$. the average of marks of the girls in the class is $80$ and that of boys is $60$. What is the percentage of boys in the class?

• A. $40\%$
• B. $60\%$
• C. $65\%$
• D. $70\%$

Answer 1

Answer: (B)

$60\%$

Let no of girls be$x$

no of boys be $y$

then $80x+60\frac{y}{x}+y=68$

So$x/y=\frac{2}{3}$..$=3\times \frac{100}{5}=60$