Question

the ratio of number of girls and boys in a class of 30 students is 7:8. if 5 new boys students admit in the class. what will be the ratio of number of girls and boys ?​

Answer 1

Given:

The ratio of number of girls and boys in a class of 30 students is 7:8

To Find:

The ratio of number of girls and boys if 5 new boys admit in the class.

Assumption:

Let the number of students be x.

Solution:

According to the question,

7x + 8x = 30

or, 15x = 30

or, x =
`\large {\tt {(30)/(15)}}`

or, x = 2

7x = 7(2) = 14

8x = 8(2) = 16

There were 14 boys and 16 girls in the school.

After admitting 5 new boys, we get

14 + 5 = 19

The ratio of number of girls and boys now is 16:19.

Answer:

16:19