A) 40
B) 20
C) 80
D) 60
Correct Answer: C
Solution :
Total number of boys and girls = Average \[\times \] Number of boys + Average \[\times \] Number of girls. Let the number of boys and girls be\[x\]and y. \[\therefore \]\[52x+42y=50(x+y)\] \[\Rightarrow \]\[52x+42y=50x+50y\] \[\Rightarrow \]\[2x=8y\]\[\Rightarrow \]\[x=4y\] \[\therefore \]Total number of students in the class \[=x+y=4y+y=5y\] \[\therefore \] Required percentage of boys \[=\frac{4y}{5y}\times 100%=80%\]You need to login to perform this action.
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