PSLE The pupils at a school choir are divided in Team A and Team B. The ratio of the number of girls to boys in Team A is 4 : 3. The ratio of the number of girls to boys in Team B is 13 : 1. There are 4 times as many pupils in Team B as in Team A. There are 242 more girls in Team B than Team A. What is the total number of boys?
Team A |
Team B |
7 u |
14x2 = 28 u |
Girls |
Boys |
Girls |
Boys |
4 u |
3 u |
13x2 = 26 u |
1x2 = 2 u
|
Total number of pupils in Team A
= 4 u + 3 u
= 7 u
Total number of pupils in Team B
= 4 x 7 u
= 28 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 28 and 14 is 28.
Number of more girls in Team B than Team A
= 26 u - 4 u
= 22 u
22 u = 242
1 u = 242 ÷ 22 = 11
Total number of boys
= 3 u + 2 u
= 5 u
= 5 x 11
= 55
Answer(s): 55