boys in a class of
(a) What is the ratio of boys to girls?
(b) What is the ratio of girls to all students in the class?
If there are 5 boys in 12 person class then there are 12-5 = 7 girls
ratio of boys to girls would be 5:7
ratio of girls to all students would then be 7:12
Well, since there are 5 boys of 12 students, we can subtract the total amount of students by the amount of boys to find the girls:
12 - 5 = 7.
Now that we know the amount of girls and boys, the ratio of boys to girls is:
a) 5 : 7.
And girls to all students is:
b) 7 : 12