1. The process capability measures Cp and Cpk differ because
A) Only one ensures the process mean is centered within the limits
B) Cp values above 1 indicate a capable process; Cpk values above 2 indicate a capable process
C) both are identical
D) Cp values for a given process will always be greater than or equal to Cpk values
E) both A and D
2. A nationwide parcel delivery service keeps track of the number of late deliveries (more than 30 minutes past the time promised to clients) per day. They plan on using a control chart to plot their results. Which type of control chart(s) would you recommend?
A)
- and R-charts
B) p-charts
C) c-charts
D)
-, but not R-charts
E) Both p- and c-charts
3. The mean and standard deviation for a process for which we have a substantial history are µ = 120 and σ = 2. For the x-bar chart, a sample size of 16 will be used. What is the mean of the sampling distribution?
A) 1/8 (0.125)
B) 7.5
C) 2
D) 40
E) 120
4. A manager wants to build 3-sigma control limits for a process. The target value for the mean of the process is 10 units, and the standard deviation of the process is 6. If samples of size 9 are to be taken, the UCL and LCL will be
A) -8 and 28
B) 16 and 4
C) 12 and 8
D) 4 and 16
E) 8 and 12

5. A process that is assumed to be in control with limits of 89 +/- 2 had sample averages of the following 87.1, 87, 87.2, 89, 90, 89.5, 88.5, and 88. Is the process in control?
A) Yes
B) No, one or more averages exceeded the limits.
C) Not enough information to tell.
D) No, there is a distinguishable trend.
E) No, two or more consecutive points are very near the lower (or upper) limit.
6. The specification for a plastic handle calls for a length of 6.0 inches ± .2 inches. The standard deviation of the process is estimated to be 0.05 inches. What are the upper and lower specification limits for this product? The process is known to operate at a mean thickness of 6.1 inches. What is the Cp and Cpk for this process? Answer: LSL = 5.8 inches, USL = 6.2 inches. Cp is 1.33, and Cpk is .67.
A) True
B) False