Question

The number of boys and girls in a 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?
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Answer 1

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

According to the given condition, we have

Number of boys = Number of girls +8

⇒7x=5x+8

⇒7x−5x=8 ....[Transposing 5x to LHS]

⇒2x=8

⇒x=

2

8

=4

Therefore, number of boys =7×4=28 and number of girls =5×4=20

So, total number of children in the class =28+20=48.

Hence, the class strength 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