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 7 : 5. The ratio of the number of girls to boys in Team B is 7 : 1. There are 2 times as many pupils in Team B as in Team A. There are 154 less girls in Team A than Team B. What is the total number of pupils in Team A?
Team A |
Team B |
12 u |
8x3 = 24 u |
Girls |
Boys |
Girls |
Boys |
7 u |
5 u |
7x3 = 21 u |
1x3 = 3 u
|
Total number of pupils in Team A
= 7 u + 5 u
= 12 u
Total number of pupils in Team B
= 2 x 12 u
= 24 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 24 and 8 is 24.
Number of less girls in Team A than Team B
= 21 u - 7 u
= 14 u
14 u = 154
1 u = 154 ÷ 14 = 11
Total number of pupils in Team A
= 7 u + 5 u
= 12 u
= 12 x 11
= 132
Answer(s): 132