Question

The no. of boys in a class is 4 less than the no. of girls . If the class strength is 40 , find the no. of boys and girls in the class?

Answer 1

According to the given question we have to find the number of boys and girls in the class.

Let, the number of girls be 'x',

And the number of boys be 'y'

$=>x+y=40...(1)$

$=>y=x-4...(2)$

By putting the value of y in equation (1),

$=>x+(x-4)=40$

$=>x+x-4=40$

$=>2x-4=40$

$=>2x=40+4$

$=>2x=44$

$=>x=22$

Now, putting the value of x in the equation (2),

$=>y=22-4\\=>y=18$

Hence, the number of boys in the class is 18 and the number of girls in the class is 22.

Answer 2

Given,

The number of boys in a class are $4$ less than the number of girls.

Let $a$ be  the number of girls in the class.

Now the number of boys will be $a-4$

Total number of students in class are $40$

$a+a-4=40$

$2a-4=40$

$2a=40+4$

$2a=44$

$a=22$

The number of girls in a class are $22$

The number of boys in a class are $a-4$

$=22-4$

$=18$

Therefore, the number of girls in a class are $22$ and the number of boys in a class are $18$