Problem:

PART ONE:

Susan's Sub Shop makes customer submarine sandwiches to order. There are 4 workers. The general flow of the process is:

[Stage A] Alex takes orders. It takes her 2 minutes to take an order.

[Stage B] Brittany slides the bun and adds meat/cheese. It takes 4 minutes per order .

[Stage C] Chelan adds toppings and condiments. It takes 5 minutes per order .

[Stage D] Dale bags the order. It takes 1 minute .

Susan wants to figure out the following:

Required:

Question 1) What is the current maximum output of Susan's Sub Shop in number of units per hour?

Question 2) Which stage is the bottleneck?

Question 3) If we add another person, to which stage would we assign her?

Question 4) After we assign another per son to the stage you answered in part c, what is the capacity of Susan's Sub Shop? Which stage is the new bottleneck? Assume it takes the new person the same amount of time as the existing person.

Question 5) Hiring a new person turns out to be very expensive, so Susan decided not to hire her. Instead, Susan decided to cross-train all the 4 current workers. After cross training, each worker can work on all the 4 stages. What is the capacity of Susan's Sub Shop?

PART TWO:

I-mart is a discount optical shop that can fill most prescription orders in about one hour. The management is analyzing the processes at the store. There currently is one person assigned to each task below.

A - Greeting the patient - 2 minutes/patient

B - Optometrist conducts eye exam - 25 minutes/patient

C - Frame/lenses selection - 20 minutes/patient

D - Glasses made (process can run 2 pairs of glasses at the same time) - 60 minutes/patient

E - Final fitting - 5 minutes/patient

Required:

Question 1) What is the current maximum output of the process per hour, assuming every patient requires glasses? Which task is the bottleneck?

After more careful analysis, I-mart learned that not all patients need glasses. For the next two parts, assume 20% of the incoming patients will leave after eye examination.

Question 2) What is the capacity of I-mart in patients per hour (including those who need glasses and those who don't.)? Which stage is the bottleneck?

Question 3) What is the capacity of I-mart in number of pairs of glasses per hour? Which stage is the bottleneck? Provide thorough explanation of every question given in the problem.