Some passengers board a school bus.
At Bus Stop A,
13 of them alight
and 7 passengers board.
At Bus Stop B,
35 of the passengers alight
and 2 board.
If there are 8 passengers on the bus now,
how many passengers are on the bus at first?
|
Number of passengers |
Before |
3 u |
|
Change 1 At Bus Stop A |
- 1 u + 7 |
|
After 1 |
2 u + 7 |
5 p |
Change 2 At Bus Stop B |
|
- 3 p + 2 |
After 2 |
|
8 |
Working backwards.
Number of passengers in the end = 8
5 p - 3 p = 8 - 2
2 p = 6
1 p = 6 ÷ 2 = 3
5 p = 5 x 3
5 p = 15
2 u + 7 = 5 p
2 u + 7 = 15
2 u = 15 - 7
2 u = 8
1 u = 8 ÷ 2 = 4
Total number of passengers at first
= 3 u
= 3 x 4
= 12
Answer(s): 12