Question 389580

Let no. of girls in class is X, then no. of boys is X+4.

thus total  2X+4 students.


according to question, 1/3 of girls and 7/11 of boys form the half of class 


X/3 + (X+4)*7/11 = (2X+4)/2



=> [ 11X + 21(X+4) ]/33 = (2X+4)/2

=>  ( 32X + 84 )/33 = (2X+4)/2


=>  64X + 168 = 66X + 132

=>   2X = 36 

=>  X = 36/2 =18 


so, 18  girls and 22 boys, total 40.