An event has a known distribution of completion times, and is repeated n times.
How would you calculate the probability of the total time being less than or equal to a specified time.
$$P((Time_1 + Time_2 + ... + Time_n)\leq X)$$
For example say that each event's time is exponentially distributed with an expected rate of 1.25 minutes per event, and you want to find the probability of completing the task 400 times in less than or equal to 500 minutes. The events are completed consecutively, one at a time.
