Question

The number of students in a class is 60. The number of boys is seven-fifths the number of girls. Find the number of boys in the class.

Answer 1

Step-by-step explanation:

Let the number of girls = x

Therefore, no. of boys = $\frac{7}{5} \times x$

$\because \: no \: of \: boys + no \: of \: girls \: = 60 \\ \\ \therefore \: \frac{7}{5} x + x = 60 \\ \\ \therefore \: \frac{7x + 5x}{5} = 60 \\ \\ \therefore \: \frac{12x}{5} = 60 \\ \\ \therefore \: x = 60 \times \frac{5}{12} \\ \\ \therefore \: x = 5 \times 5 \\ \\ \therefore \: x = 25 \\ \\ \therefore \: \frac{7}{5} x = \frac{7}{5} \times 25 = 7 \times 5 = 35$

Thus, no of boys in the class is 35.