When a bus arrives at a station, 4 / 7 of all passengers get off and 33 passengers come up. At this time, the number of passengers on the bus is 5 / 6 of the original number. How many passengers are there?

There are x original passengers
So after 4 / 7 people get off, there are (3 / 7 * x) people left on the bus
After another 33 people came up, there were (3 / 7 * x + 33) people on board
If it's equal to the original 5 / 6, it's 5 / 6 * x people
Equation: 3 / 7 * x + 33 = 5 / 6 * x
The linear equation of one variable is solved, and X is 81.52
But because there is no decimal point in the number of people,
So the conclusion is that there is a number error in the middle of your topic

Arrangement and combination: a bus has five stops. How many ways do seven passengers get off the bus?

The answer is to the 5th power of 7! There are seven ways to get off at every station! So it's 7 * 7 * 7 * 7 * 7 * 7 = 7 ^ 5

When the bus departs, there are 72 people on board. At a station, the male passengers get off 1 / 8 and the female passengers get on 3. At this time, the number of male and female passengers is equal, so it is necessary to calculate the original number
How many male and female passengers

Male passenger: (72 + 3) / {(1 + (1-1 / 8)} = 40
Female passenger: 72-40 = 32 (person)
A: there are 40 male passengers and 32 female passengers

A bus has (5a-4) passengers, get off at a station (9-2a), ask how many people on the bus!

The title is ambiguous
There were (5a-4) passengers, and they got off at a station (9-2a). Then there were (5a-4) passengers
Understanding 2. There are (5a-4) passengers who get off at a station (9-2a), then the original number is
(5a-4) + (9-2a) = 3A + 5
3. There are (5a-4) passengers getting off at a station (9-2a);
4. There are (5a-4) passengers getting off at a station (9-2a);
The third and fourth understandings are unanswerable
In fact, the expression of this question is really not good

When a bus arrives at a station, 4 / 7 of all passengers get off and 33 passengers come up. At this time, the number of passengers on the bus is 5 / 6 of the original number. How many passengers are there?