Question

In June-2020, the ratio of boys to girls in a college was 3 : 2. In September-2020, there were 80 fewer boys and 20 fewer girls in the college and the ratio of boys to girls was 7 : 5. What was the total number of students in the college in June-2020?

Accepted Answer

D. Let the number of boys and girls in June-2020 be $3x$ and $2x$ respectively. In September-2020: - Number of boys = $3x - 80$ - Number of girls = $2x - 20$ Given ratio: $$\frac{3x - 80}{2x - 20} = \frac{7}{5}$$ $$5(3x - 80) = 7(2x - 20)$$ $$15x - 400 = 14x - 140$$ $$x = 260$$ Total students in June-2020 = $3x + 2x = 5x = 5 	imes 260 = 1300$.

Ratio of boys and girls in college

Explanation

Practise this under exam conditions