Some students board a school bus.
At Bus Stop A,
27 of them alight
and 2 students board.
At Bus Stop B,
14 of the students alight
and 6 board.
If there are 15 students on the bus now,
how many students are on the bus at first?
|
Number of students |
Before |
7 u |
|
Change 1 At Bus Stop A |
- 2 u + 2 |
|
After 1 |
5 u + 2 |
4 p |
Change 2 At Bus Stop B |
|
- 1 p + 6 |
After 2 |
|
15 |
Working backwards.
Number of students in the end = 15
4 p - 1 p = 15 - 6
3 p = 9
1 p = 9 ÷ 3 = 3
4 p = 4 x 3
4 p = 12
5 u + 2 = 4 p
5 u + 2 = 12
5 u = 12 - 2
5 u = 10
1 u = 10 ÷ 5 = 2
Total number of students at first
= 7 u
= 7 x 2
= 14
Answer(s): 14