33 Primary 3 students and 28 of Primary 4 students went on a school learning journey. The number of Primary 4 boys was 3 times the number of Primary 3 boys, and there were 15 more Primary 3 girls than Primary 4 girls. How many more Primary 4 boys than Primary 4 girls went on the school learning journey?
| Primary 3 |
Primary 4 |
| 33 |
28 |
| Boys |
Girls |
Boys |
Girls |
| 1 u |
1 p + 15 |
3 u |
1 p |
Total number of students in Primary 3 = 1 u + 1 p + 15
1 u + 1 p + 15 = 33
1 u + 1 p = 33 - 15
1 u + 1 p = 18 --- (1)
Total number of students in Primary 4 = 3 u + 1 p
3 u + 1 p = 28 --- (2)
(2) - (1)
(3 u + 1 p) - (1 u + 1 p) = 28 - 18
3 u - 1 u = 10
2 u = 10
1 u = 10 ÷ 2 = 5
Number of boys in Primary 4
= 3 u
= 3 x 5
= 15
Number of girls in Primary 4
= 1 p
= 28 - 3 u
= 28 - 15
= 13
Number of more boys than girls in Primary 4
= 15 - 13
= 2
Answer(s): 2
