22 Primary 4 students and 13 of Primary 5 students went on a school learning journey. The number of Primary 5 boys was 5 times the number of Primary 4 boys, and there were 17 less Primary 5 girls than Primary 4 girls. How many less Primary 5 girls than Primary 5 boys went on the school learning journey?
| Primary 4 |
Primary 5 |
| 22 |
13 |
| Boys |
Girls |
Boys |
Girls |
| 1 u |
1 p + 17 |
5 u |
1 p |
Total number of students in Primary 4 = 1 u + 1 p + 17
1 u + 1 p + 17 = 22
1 u + 1 p = 22 - 17
1 u + 1 p = 5 --- (1)
Total number of students in Primary 5 = 5 u + 1 p
5 u + 1 p = 13 --- (2)
(2) - (1)
(5 u + 1 p) - (1 u + 1 p) = 13 - 5
5 u - 1 u = 8
4 u = 8
1 u = 8 ÷ 4 = 2
Number of boys in Primary 5
= 5 u
= 5 x 2
= 10
Number of girls in Primary 5
= 1 p
= 13 - 5 u
= 13 - 10
= 3
Number of less girls than boys in Primary 5
= 10 - 3
= 7
Answer(s): 7
