Arrivals of customers at a telephone booth follow poisson distribution, with an average time
of 10 minutes between one arrival and the next. The length of the phone call is assumed to be
distributed exponentially with a mean of 3 minutes. Find
The average number of persons waiting and making telephone calls
The average length of the queue that is formed from time to time.
Probability that a customer arrive and find telephone booth is busy.
Probability that a customer arrive and find telephone booth is empty.
The average time spent by a customer in telephone booth
a.
b.
d.
e.