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