23 Primary 5 pupils and 14 of Primary 6 pupils went on a school outing. The number of Primary 6 boys was 4 times the number of Primary 5 boys, and there were 15 more Primary 5 girls than Primary 6 girls. How many more Primary 6 boys than Primary 6 girls went on the school outing?
| Primary 5 |
Primary 6 |
| 23 |
14 |
| Boys |
Girls |
Boys |
Girls |
| 1 u |
1 p + 15 |
4 u |
1 p |
Total number of pupils in Primary 5 = 1 u + 1 p + 15
1 u + 1 p + 15 = 23
1 u + 1 p = 23 - 15
1 u + 1 p = 8 --- (1)
Total number of pupils in Primary 6 = 4 u + 1 p
4 u + 1 p = 14 --- (2)
(2) - (1)
(4 u + 1 p) - (1 u + 1 p) = 14 - 8
4 u - 1 u = 6
3 u = 6
1 u = 6 ÷ 3 = 2
Number of boys in Primary 6
= 4 u
= 4 x 2
= 8
Number of girls in Primary 6
= 1 p
= 14 - 4 u
= 14 - 8
= 6
Number of more boys than girls in Primary 6
= 8 - 6
= 2
Answer(s): 2
