Class 2 Joy and 2 Peace had the same number of students. The ratio of the number of boys in 2 Joy to the number of boys in 2 Peace was 5 : 7. The ratio of the number of girls in 2 Joy to the number of girls in 2 Peace was 2 : 1.
- What is the ratio of the number of girls to the number of boys in Class 2 Joy?
- If there were 15 fewer girls than boys in Class 2 Peace, how many students were there each class?
Class 2 Joy |
Class 2 Peace |
1x9 = 9 u |
1x9 = 9 u |
Boys |
Girls |
Boys |
Girls |
5 |
2x2 |
7 |
1x2 |
5 u |
4 u |
7 u |
2 u |
(a)
Class 2 Joy
Girls : Boys
5 : 4
(b)
Number of fewer girls than boys in Class 2 Peace
= 7 u - 2 u
= 5 u
5 u = 15
1 u = 15 ÷ 5 = 3
Number of students in each class
= 9 u
= 9 x 3
= 27
Answer(s): (a) 5 : 4; (b) 27