申論題

4. Consider an automobile assembly line in which each car undergoes two types of service: painting, then engine installation. Each hour, an average of 22.4 unpainted chassis arrive at the assembly line. It takes an average of 2.4 minutes to paint a car and an average of 3.75 minutes to install an engine. The assembly line has one painter and two engine installers. Assume that interarrival times and service times are exponential.

(b) On the average, how long will a painted car have to wait before installation of its engine begins? (10%)