PSLE The pupils at a camp are divided in Team A and Team B. The ratio of the number of girls to boys in Team A is 5 : 4. The ratio of the number of girls to boys in Team B is 5 : 1. There are 2 times as many pupils in Team B as in Team A. There are 150 less girls in Team A than Team B. What is the total number of pupils in Team A?
Team A |
Team B |
9 u |
6x3 = 18 u |
Girls |
Boys |
Girls |
Boys |
5 u |
4 u |
5x3 = 15 u |
1x3 = 3 u
|
Total number of pupils in Team A
= 5 u + 4 u
= 9 u
Total number of pupils in Team B
= 2 x 9 u
= 18 u
The total number of pupils in Team B is repeated.
Use LCM to make the total number of pupils in Team B the same.
LCM of 18 and 6 is 18.
Number of less girls in Team A than Team B
= 15 u - 5 u
= 10 u
10 u = 150
1 u = 150 ÷ 10 = 15
Total number of pupils in Team A
= 5 u + 4 u
= 9 u
= 9 x 15
= 135
Answer(s): 135