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 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 66 more girls in Team B than Team A. What is the total number of pupils?

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 = 66

1 u = 66 ÷ 22 = 3

Total number of pupils
= 4 u + 3 u + 26 u + 2 u
= 35 u
= 35 x 3
= 105

Answer(s): 105