22 Primary 2 pupils and 16 of Primary 3 pupils went on a school outing. The number of Primary 3 boys was 5 times the number of Primary 2 boys, and there were 18 more Primary 2 girls than Primary 3 girls. How many less Primary 3 girls than Primary 3 boys went on the school outing?
| Primary 2 |
Primary 3 |
| 22 |
16 |
| Boys |
Girls |
Boys |
Girls |
| 1 u |
1 p + 18 |
5 u |
1 p |
Total number of pupils in Primary 2 = 1 u + 1 p + 18
1 u + 1 p + 18 = 22
1 u + 1 p = 22 - 18
1 u + 1 p = 4 --- (1)
Total number of pupils in Primary 3 = 5 u + 1 p
5 u + 1 p = 16 --- (2)
(2) - (1)
(5 u + 1 p) - (1 u + 1 p) = 16 - 4
5 u - 1 u = 12
4 u = 12
1 u = 12 ÷ 4 = 3
Number of boys in Primary 3
= 5 u
= 5 x 3
= 15
Number of girls in Primary 3
= 1 p
= 16 - 5 u
= 16 - 15
= 1
Number of less girls than boys in Primary 3
= 15 - 1
= 14
Answer(s): 14
