Sanchez Trucking has been experiencing delays at its warehouse operations. Management hired a consultant to find out why service deliveries to local businesses have taken longer than they should. The consultant narrowed down the problem to the number of work crews loading and unloading trucks. Each crew consists of 6 employees who work as a team on a variety of tasks; each employee works a full 40 hours a week. However, costs are also a concern. The consultant advised management that they could supplement work crews with short-term employees, at a higher cost, to cover unexpected needs on a weekly basis. Each work crew permanently hired by Sanchez costs $2,800 per week in wages and benefits, while a crew of short-term employees costs $5,500 per week. Complicating the decision is the fact that the weekly hourly requirements for work crews is uncertain because of the volatility in the number of deliveries to be made. Deliberating with management, the consultant arrived at the following data. 960 1,200 Requirements (man-hours) Probability 480 720 0.1 0.5 0.3 0.1 Number of crews 2 3 4 If the consultant wants to offer a solution that minimizes the expected weekly costs for Sanchez, how many work crews should Sanchez have on its permanent payroll? A payroll containing work crews is the lowest cost alternative, with expected weekly costs to Sanchez of $. (Enter your responses as integers.)

Ripeka, the warehouse manager at Hine would like to update the company’s inventory locator system so that the picking operation can be streamlined. While conceptually simple to do, she knows that there will be several steps to the update process that will have to be carefully managed. She needs to complete upgrade and train her staff in operating the new system before the busy season, which is only 4 months away. She identifies the various activities, expected time duration, predecessors and costs, as shown in the table. Draw the AON Network, and then determine the critical path. [Show your workings, using the grid network.] Identify the project duration – is this project feasible within the required timeframe?

L. Winston Martin (an allergist) has an excellent system for handling his regular patients who come in just for allergy injections. Patients arrive for an injection and fill out a name slip, which is then placed in an open slot that passes into another room staffed by one or two nurses. The specific injections for a patient are prepared, and the patient is called through a speaker system into the room to receive the injection. At certain times during the day, patient load drops and only one nurse is needed to administer the injections. Use Exhibit 712. Let's focus on the simpler case of the two-namely, when there is one nurse. Also, assume that patients arrive in a Poisson fashion and the service rate of the nurse is exponentially distributed. During this slower period, patients arrive with an interarrival time of approximately 3 minutes. It takes the nurse an average of 2.50 minutes to prepare the patients' serum and administer the injection. a. What is the average number of patients…

Stooge Enterprises (Stooges) manufactures wooden mallets for commercial and residentialapplications. Stooges landed a major contract as a supplier to Slapsticks, Inc., a leading retailer inseveral major cities throughout the upper Midwest. Because of the large volume of demand,Stooges has to expand its manufacturing operation to three shifts and hire additional workers.Not long after Stooges began mallets to Slapsticks, it began receiving some complaints about mallethead diameters. This problem was somewhat alarming to Stooges, because its reputation as a highquality manufacturer was the principal reason that it was selected as a supplier to Slapsticks.Stooges placed a great deal of confidence in its manufacturing capability because of its well trainedand dedicated employees, and it never felt the need to consider formal process control approaches.In view of the recent complaints, the company president suspected that the expansion to a three-shift operation and the pressures to produce…