PSLE The students at a sports meet are divided in Team A and Team B. The ratio of the number of boys to girls in Team A is 3 : 1. The ratio of the number of boys to girls in Team B is 7 : 3. There are 5 times as many students in Team B as in Team A. There are 143 more boys in Team B than Team A. What is the total number of girls?
Team A |
Team B |
4 u |
10x2 = 20 u |
Boys |
Girls |
Boys |
Girls |
3 u |
1 u |
7x2 = 14 u |
3x2 = 6 u
|
Total number of students in Team A
= 3 u + 1 u
= 4 u
Total number of students in Team B
= 5 x 4 u
= 20 u
The total number of students in Team B is repeated.
Use LCM to make the total number of students in Team B the same.
LCM of 20 and 10 is 20.
Number of more boys in Team B than Team A
= 14 u - 3 u
= 11 u
11 u = 143
1 u = 143 ÷ 11 = 13
Total number of girls
= 1 u + 6 u
= 7 u
= 7 x 13
= 91
Answer(s): 91