Question

1. In school hall, there were 65 fewer boys than girls.After 2/5 of the boys and 3/7 of the girls left the hall for recess, there were equal number of boys and girls that remained in the hall. Find the total number of students that remained in the Hall in the end.

Answer 1

Step-by-step explanation:

Let the no. of girls be x

No. of boys = x-65

After 2/5 of the boys and 3/7 of the girls left the hall

No. of boys = x-65-(2/5 of x)

= x-65- 2x/5

= x-2x/5-65

= 3x/5-65

No. of girls = x-(3/7 of x)

= x-3x/7

= 7x-3x/7

= 4x/7

By condition,

3x/5-65 = 4x/7

3x/5+4x/7 = 65

21x+20x/35 = 65

41x/35 = 65

x = 65×35/41