Some adults board a school bus.
At Bus Stop A,
35 of them alight
and 2 adults board.
At Bus Stop B,
49 of the adults alight
and 6 board.
If there are 16 adults on the bus now,
how many adults are on the bus at first?
|
Number of adults |
Before |
5 u |
|
Change 1 At Bus Stop A |
- 3 u + 2 |
|
After 1 |
2 u + 2 |
9 p |
Change 2 At Bus Stop B |
|
- 4 p + 6 |
After 2 |
|
16 |
Working backwards.
Number of adults in the end = 16
9 p - 4 p = 16 - 6
5 p = 10
1 p = 10 ÷ 5 = 2
9 p = 9 x 2
9 p = 18
2 u + 2 = 9 p
2 u + 2 = 18
2 u = 18 - 2
2 u = 16
1 u = 16 ÷ 2 = 8
Total number of adults at first
= 5 u
= 5 x 8
= 40
Answer(s): 40