Answer:
a) 11 : 20
b) 9 : 11
c) 9 : 20
Explanation:
500: total number of students
275: total number of boys
500 - 275 = 225: total number of girls
then:
a) the boys to the total number of students:
275:500 = 11:20
b) the girls to that of the boys.
225:275 = 9:11
c) the girls to the total number of students
225: 500 = 9:20
