Question

Please give answers.



No. 14.​

Answer 1

Let total student be x

A/q

girls are 3/7of student

so,

3 x/7

boys =240

total no. of student = total girls +total boys

x = 3x/7+240

x = (3x+1680)/7

by cross multiplication

7x = 3x +1680

7x-3x = 1680

4x= 1680

x= 1680/4

x =420

now we know that girls are 3/7 of total students

girls =3/7×420

girls = 180

Answer 2

solution

let number of students be x.

Number of girls =3/7 of x

3/7x

number of boys = 240

number of boys + number of girls = tolal student

240 + 3/7x = x

240 = x - 3/7x

240 = 4x/7

240 × 7 = 4x

1680 = 4x

1680 ÷ 4 =x

420 = x

total student = 420

Number of girls = 420 - 240

= 200

so number of girls = 200