33 Primary 3 students and 26 of Primary 4 students went on a school outing. The number of Primary 4 girls was 3 times the number of Primary 3 girls, and there were 19 more Primary 3 boys than Primary 4 boys. How many less Primary 4 boys than Primary 4 girls went on the school outing?
| Primary 3 |
Primary 4 |
| 33 |
26 |
| Girls |
Boys |
Girls |
Boys |
| 1 u |
1 p + 19 |
3 u |
1 p |
Total number of students in Primary 3 = 1 u + 1 p + 19
1 u + 1 p + 19 = 33
1 u + 1 p = 33 - 19
1 u + 1 p = 14 --- (1)
Total number of students in Primary 4 = 3 u + 1 p
3 u + 1 p = 26 --- (2)
(2) - (1)
(3 u + 1 p) - (1 u + 1 p) = 26 - 14
3 u - 1 u = 12
2 u = 12
1 u = 12 ÷ 2 = 6
Number of girls in Primary 4
= 3 u
= 3 x 6
= 18
Number of boys in Primary 4
= 1 p
= 26 - 3 u
= 26 - 18
= 8
Number of less boys than girls in Primary 4
= 18 - 8
= 10
Answer(s): 10
