You are the newly appointed assistant administrator at a local hospital, and your first project is to investigate the quality of the patient meals put out by the food-service department. You conducted a 10-day survey by submitting a simple questionnaire to the 400 patients with each meal, asking that they simply check off either that the meal was satisfactory or unsatisfactory. For simplicity in this problem, assume that the response was 1,000 returned questionnaires from the 1,200 meals each day. The results ran as follows:
Date in December # of Unsatisfactory Meals Sample Size
1 74 1,000
2 42 1,000
3 64 1,000
4 80 1,000
5 40 1,000
6 50 1,000
7 65 1,000
8 70 1,000
9 40 1,000
10 75 1,000
Total 600 10,000
Use this data to determine the upper and lower control limits
Is this process in control?