Question

There are $20$ girls and $15$ boys in a class. What is the ratio of number of girls to the total number of students in the class?

Answer 1

Number of girls = $20$

Number of boys = $15$

Total number of students$=20+15=35$

$\begin{array}{rcl}\mathrm{Ratio}\mathrm{of}\mathrm{number}\mathrm{of}\mathrm{girls}\mathrm{to}\mathrm{the}\mathrm{total}\mathrm{number}\mathrm{of}\mathrm{students}\mathrm{in}\mathrm{the}\mathrm{class}& =& \frac{\mathrm{Number}\mathrm{of}\mathrm{girls}}{\mathrm{Total}\mathrm{number}\mathrm{of}\mathrm{students}}\\ & =& \frac{20}{35}\\ & =& \frac{4}{7}\\ & =& 4:7\end{array}$

Hence, required ratio = $4:7$.