Question

the number of boys and girls in class are in ratio 7 ratio 5 the number of boys is 8 more than number of girls what is the total class strength​

Answer 1

GIVEN :-

• Ratio of number of boys to number of girls is 7:5
• Number of boys is 8 more than Number of girls

TO FIND :-

• Total strength of the class

SOLUTION :-

Let

• Number of boys be 7x
• Number of girls be 5x

We are given,

Number of boys is 8 more than Number of girls

$\implies \sf \: 7x = 5x + 8 \\ \\ \implies \sf \: 7x - 5x = 8 \\ \\ \implies \sf \: 2x = 8 \\ \\ \implies \sf \: x = \frac{8}{2} \\ \\ \implies {\underline {\bold {\boxed {\pink {\sf{x = 4}}}}}}$

Then ,

$\sf \: Number \: of \: boys \: = 7x = 7(4) = 28 \\ \\ \sf Number \: of \: girls = 5x = 5(4) = 20$

Total class strength = Number of girls + Number of boys

$\implies \sf \: Total \: class \: strength = 20 + 28 \\ \\ \implies {\underline {\bold {\boxed {\blue {\sf{Total \: class\: strength \: = 48}}}}}}$

∴ Total Strength of the class is 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