Some passengers board a school bus.
At Bus Stop A,
17 of them alight
and 3 passengers board.
At Bus Stop B,
49 of the passengers alight
and 2 board.
If there are 17 passengers on the bus now,
how many passengers are on the bus at first?
|
Number of passengers |
Before |
7 u |
|
Change 1 At Bus Stop A |
- 1 u + 3 |
|
After 1 |
6 u + 3 |
9 p |
Change 2 At Bus Stop B |
|
- 4 p + 2 |
After 2 |
|
17 |
Working backwards.
Number of passengers in the end = 17
9 p - 4 p = 17 - 2
5 p = 15
1 p = 15 ÷ 5 = 3
9 p = 9 x 3
9 p = 27
6 u + 3 = 9 p
6 u + 3 = 27
6 u = 27 - 3
6 u = 24
1 u = 24 ÷ 6 = 4
Total number of passengers at first
= 7 u
= 7 x 4
= 28
Answer(s): 28