Question

In a class of 100 students, there are 45 boys. What is the ratio of the number of girls to total number of students in that class? (2 marks)

Answer 1

Total number of students = 100
Number of boys = 45
Number of girls = 100 - 45 = 55
(1 mark)
The ratio of the number of girls to total number of students = $\frac{55}{100}$ = $\frac{11}{20}$
(1 mark)

Hence, the the ratio of the number of girls to total number of students in that class is 11:20.