Some passengers board a school bus.
At Bus Stop A,
35 of them alight
and 11 passengers board.
At Bus Stop B,
35 of the passengers alight
and 2 board.
If there are 12 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 |
- 3 u + 11 |
|
After 1 |
2 u + 11 |
5 p |
Change 2 At Bus Stop B |
|
- 3 p + 2 |
After 2 |
|
12 |
Working backwards.
Number of passengers in the end = 12
5 p - 3 p = 12 - 2
2 p = 10
1 p = 10 ÷ 2 = 5
5 p = 5 x 5
5 p = 25
2 u + 11 = 5 p
2 u + 11 = 25
2 u = 25 - 11
2 u = 14
1 u = 14 ÷ 2 = 7
Total number of passengers at first
= 5 u
= 5 x 7
= 35
Answer(s): 35