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 7 : 3. The ratio of the number of boys to girls in Team B is 8 : 7. There are 3 times as many students in Team B as in Team A. There are 36 more boys in Team B than Team A. What is the total number of girls?

Team A		Team B
10 u		15x2 = 30 u
Boys	Girls	Boys	Girls
7 u	3 u	8x2 = 16 u	7x2 = 14 u

Total number of students in Team A
= 7 u + 3 u
= 10 u

Total number of students in Team B
= 3 x 10 u
= 30 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 30 and 15 is 30.

Number of more boys in Team B than Team A
= 16 u - 7 u
= 9 u

9 u = 36

1 u = 36 ÷ 9 = 4

Total number of girls
= 3 u + 14 u
= 17 u
= 17 x 4
= 68

Answer(s): 68