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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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Solution
Let the common ratio between the number of boys and numbers of girls be x.
Number of boys = 7x
Number of girls = 5x
According to the given question,
Number of boys = Number of girls + 8
∴ 7x = 5x + 8
On transposing 5x to L.H.S, we obtain
7x − 5x = 8
2x = 8
On dividing both sides by 2, we obtain
`(2x)/2 = 8/2`
x = 4
Number of boys = 7x = 7 × 4 = 28
Number of girls = 5x = 5 × 4 = 20
Hence, total class strength = 28 + 20 = 48 students.
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