In a bank drive-through, there is a single service window and room only for two cars to line-up to wait for service. The mean time between arrivals for drive through customers is 5 minutes. The mean time to complete a customer transaction is 3 minutes. The number of arrivals is distributed according to a Poisson distribution and the service times are exponentially distributed.
- What is the probability that there are no vehicles in the system?
- On average how many cars are in the system?
- What is the probability that the system is full and new arrival must drive on?
- What is the average time a customer spends in waiting in line to be served?