22 Primary 5 pupils and 13 of Primary 6 pupils went on a school camp. The number of Primary 6 boys was 5 times the number of Primary 5 boys, and there were 17 more Primary 5 girls than Primary 6 girls. How many more Primary 6 boys than Primary 6 girls went on the school camp?
| Primary 5 |
Primary 6 |
| 22 |
13 |
| Boys |
Girls |
Boys |
Girls |
| 1 u |
1 p + 17 |
5 u |
1 p |
Total number of pupils in Primary 5 = 1 u + 1 p + 17
1 u + 1 p + 17 = 22
1 u + 1 p = 22 - 17
1 u + 1 p = 5 --- (1)
Total number of pupils in Primary 6 = 5 u + 1 p
5 u + 1 p = 13 --- (2)
(2) - (1)
(5 u + 1 p) - (1 u + 1 p) = 13 - 5
5 u - 1 u = 8
4 u = 8
1 u = 8 ÷ 4 = 2
Number of boys in Primary 6
= 5 u
= 5 x 2
= 10
Number of girls in Primary 6
= 1 p
= 13 - 5 u
= 13 - 10
= 3
Number of more boys than girls in Primary 6
= 10 - 3
= 7
Answer(s): 7
