1. A process is in statistical control with the process mean of 100 and S.D. of 3. Specifications are at 100 ± 10. Compute the process capability ratio. Is the process capable?
2. A process is in statistical control with the process mean of 100 and S.D. of 3. Specifications with tolerance ranges are 100 ± 10. The process mean is exactly centered on the target value. Compute the process capability ratio. Is the process capable? Explain.
3. Tom Consumer Advocates, Inc. checks products for proper labeling with regard to the amount of product in the container. A problem has come to their attention concerning New York Orange Juice. They wish to purchase some of the product to evaluate whether or not the complaints are justified. They decide that the acceptable quality level of under-filled containers is 1% and they would tolerate no more than 3%. They want a sampling plan that will not accuse New York Orange Juice falsely more than 5% of the time and not fail to recognize the problem (if it exists) more than 8% of the time. How many containers should be purchased and how many of them are allowed to be short?
4. What is “process capability”? How can a firm generally improve process capability?
5. What does the term “in statistical control” mean?