Some students board a school bus.
At Bus Stop A,
35 of them alight
and 8 students board.
At Bus Stop B,
13 of the students alight
and 9 board.
If there are 17 students on the bus now,
how many students are on the bus at first?
|
Number of students |
Before |
5 u |
|
Change 1 At Bus Stop A |
- 3 u + 8 |
|
After 1 |
2 u + 8 |
3 p |
Change 2 At Bus Stop B |
|
- 1 p + 9 |
After 2 |
|
17 |
Working backwards.
Number of students in the end = 17
3 p - 1 p = 17 - 9
2 p = 8
1 p = 8 ÷ 2 = 4
3 p = 3 x 4
3 p = 12
2 u + 8 = 3 p
2 u + 8 = 12
2 u = 12 - 8
2 u = 4
1 u = 4 ÷ 2 = 2
Total number of students at first
= 5 u
= 5 x 2
= 10
Answer(s): 10