PSLE The pupils at a camp are divided in Team A and Team B. The ratio of the number of boys to girls in Team A is 7 : 1. The ratio of the number of boys to girls in Team B is 5 : 1. There are 3 times as many pupils in Team B as in Team A. There are 65 less boys in Team A than Team B. What is the total number of pupils in Team A?
Team A |
Team B |
8 u |
6x4 = 24 u |
Boys |
Girls |
Boys |
Girls |
7 u |
1 u |
5x4 = 20 u |
1x4 = 4 u
|
Total number of pupils in Team A
= 7 u + 1 u
= 8 u
Total number of pupils in Team B
= 3 x 8 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 6 is 24.
Number of less boys in Team A than Team B
= 20 u - 7 u
= 13 u
13 u = 65
1 u = 65 ÷ 13 = 5
Total number of pupils in Team A
= 7 u + 1 u
= 8 u
= 8 x 5
= 40
Answer(s): 40