Question

The number of boys and girls in class are in the
ratio 7:5. The number of boys is 8 more than the number of girls. What is the total class strength?​

Answer 1

$\large\green{\underline{\underline{\bf{\blue{Given}}}}}$

1. Ratio of numbers of boys and girls = 7:5

1. Number of boys is 8 more than girls

$\large\green{\underline{\underline{\bf{\blue{To Find}}}}}$

• Total class strength

$\large\green{\underline{\underline{\bf{\blue{Solution}}}}}$

Let the,

Number of Girls be 'x'

Then,

Number of Boys = ( x + 8 )

Now,

According to Question,

$\implies \: \frac{(x + 8)}{x} = \frac{7}{5} \\ \\ \implies \: 5(x + 8) = 7x \\ \\ \implies \: 5x + 40 = 7x \\ \\ \implies \: 7x - 5x = 40 \\ \\ \implies \: 2x = 40 \\ \\ \implies \: x = \frac{40}{2} = 20$

Hence,

• Number of Boys = ( x + 8) = 20 +8 = 28

• Number of Girls = x = 20

Total strength of class = Total no of boys + Total no of girls.

• Total Strength of class = 20 + 28 = 48

Answer 2

Let the number of boys be 7x and girls be 5x.

According to the question,

7x = 5x + 8

⇒ 7x – 5x = 8

⇒ 2x = 8

⇒ x = 8/2

⇒ x = 4

Therefore, Number of boys = 7×4 = 28

And, Number of girls = 5×4 = 20

Total number of students = 20+28 = 48