# Quality Assurance Assignment

7.3) Table 7E.1 Contains data on examination of medical insurance claims. Every Days 50 claims were examined. (a) Set up the fraction nonconforming control chart for this process. Plot the preliminary data in Table 7E.1 on the chart. Is the process in statistical control?

(b)Assume that assignable causes can be found for any our-of-control points on this chart. What center line and control limits should be used for process monitoring in the next period?

7.9) 7.40) A fraction nonconforming control chart with n=400 has the following parameters: UCL=0.0962, Center Line = 0.0500 and LCL = 0.0038

a. Find the width of the control limits in standard deviation units.

b. Suppose the process fraction nonconforming shifts to 0.15. What is the probability of detecting the shift on the first subsequent sample?

7.42) The following fraction nonconforming control chart with n = 100 is used to control a process:

UCL = 0.0750

Center line = 0.0400

LCL = 0.0050

1. (a) Use the Poisson approximation to the binomial to find the probability of a type I error.

2. (b) Use the Poisson approximation to the binomial to find the probability of a type II error, if the true process fraction nonconforming is 0.0600.

3. (c) Draw the OC curve for this control chart.

4. (d) Find the ARL when the process is in control and the ARL when the process fraction nonconform-nonconforming is 0.0600.