29 Primary 1 students and 19 of Primary 2 students went on a school camp. The number of Primary 2 girls was 4 times the number of Primary 1 girls, and there were 19 more Primary 1 boys than Primary 2 boys. How many less Primary 2 boys than Primary 2 girls went on the school camp?
Primary 1 |
Primary 2 |
29 |
19 |
Girls |
Boys |
Girls |
Boys |
1 u |
1 p + 19 |
4 u |
1 p |
Total number of students in Primary 1 = 1 u + 1 p + 19
1 u + 1 p + 19 = 29
1 u + 1 p = 29 - 19
1 u + 1 p = 10 --- (1)
Total number of students in Primary 2 = 4 u + 1 p
4 u + 1 p = 19 --- (2)
(2) - (1)
(4 u + 1 p) - (1 u + 1 p) = 19 - 10
4 u - 1 u = 9
3 u = 9
1 u = 9 ÷ 3 = 3
Number of girls in Primary 2
= 4 u
= 4 x 3
= 12
Number of boys in Primary 2
= 1 p
= 19 - 4 u
= 19 - 12
= 7
Number of less boys than girls in Primary 2
= 12 - 7
= 5
Answer(s): 5