Class 3 Peace and 3 Faithfulness had the same number of pupils. The ratio of the number of girls in 3 Peace to the number of girls in 3 Faithfulness was 3 : 5. The ratio of the number of boys in 3 Peace to the number of boys in 3 Faithfulness was 2 : 1.
- What is the ratio of the number of boys to the number of girls in Class 3 Peace?
- If there were 18 fewer boys than girls in Class 3 Faithfulness, how many pupils were there each class?
Class 3 Peace |
Class 3 Faithfulness |
1x7 = 7 u |
1x7 = 7 u |
Girls |
Boys |
Girls |
Boys |
3 |
2x2 |
5 |
1x2 |
3 u |
4 u |
5 u |
2 u |
(a)
Class 3 Peace
Boys : Girls
3 : 4
(b)
Number of fewer boys than girls in Class 3 Faithfulness
= 5 u - 2 u
= 3 u
3 u = 18
1 u = 18 ÷ 3 = 6
Number of pupils in each class
= 7 u
= 7 x 6
= 42
Answer(s): (a) 3 : 4; (b) 42