In how many ways can six people sit in a six-passenger car?

number of ways = 720

Step-by-step explanation:

The number of ways six people sit in a six-passenger car is given by the number of permutations of 6 elements in 6 different positions (seats), then

number of ways = number of permutations of 6 elements = 6! = 6 * 5 * 4 * 3 * 2 * 1 = 720

Since the first person that sits can be on any of the seats, but then the second person that sits can choose any of 5 seats (since the first person had already occupied one), the third can choose 4 ... and so on.