Suppose an audit process is taking place at a small airport, andthe head
auditor arrives randomly throughout the day and assesses theoperation of the airport.
She shows up in one-hr intervals at a time. The time betweenaircraft arrivals at this
small airport is exponentially distributed with a mean of 75minutes. You may assume
the operation of the small airport is independent of the timeinterval under consideration.
a) What is the probability that at least four aircrafts arrivewithin an hour?
b)What is the probability that more than three and less than sixaircrafts arrive within an
hour?
C)What is the amount of time (in hours) such that the probabilityof aircraft arrivals in the
interval is 75%?
D) What is the probability that the third interval the auditorshows up for is the second
interval with at least four aircraft arrivals?
e) If the auditor decides to show up four different times in a day,what is the mean of the
number of intervals she will experience with less than fouraircraft arrivals?
