Answer: 9 groups of riders.
Explanation:
To find out how many groups of riders there will be, you need to divide the total number of people waiting in line by the maximum number of people allowed on the ride at one time.
157 (total people in line) ÷ 17 (people allowed per ride) = 9.235 (groups of riders)
Because you can't have a fraction of a group, you need to round down to get the whole number of groups.
So the answer is 9 groups of riders.