Consider a production line with two facilities in series. (A facility is the same as a station.) Every customer or job requires service first at facility 1 and then at facility 2. The mean and std. deviation of the effective service time at facility 1 is te1 = 4 minutes and se1 = 9 minutes. The corresponding service time mean and standard deviation at facility 2 is te2 =10 minutes and se2 = 4 minutes, respectively. Service facility 1 has one server and facility 2 has two identical (parallel) servers. The desired throughput rate of the line is nine customers (jobs) per hour. The customer arrival process has moderate variability corresponding to exponential interarrival times with coefficient of variation ca = 1.0. Answer the following questions. In case time is short, provide formulas and data values you would use for your computations / calculations.

1) Compute the line’s bottleneck rate rb, the raw process time T0, and the critical WIP W0.

2) Compute the WIP level w at which the Practical Worst Case Throughput will equal 9 jobs per hour. [No need to round WIP level to an integer value.]

3) Estimate the average number of customers at facility 1.