OPERATIONS LOGISTICS MANAGEMENT
TRUE or FALSE
1. T F It is impossible to develop a process that has zero variability.
2. T F Assignable variations in a process are also called natural variations.
3. T F An x-bar chart would be appropriate to monitor the number of defects in a production lot.
4. T F The central limit theorem provides the statistical foundation for control charts.
5. T F If we are tracking quality of performance for a class of students, we should plot the pass/fail result on a p-chart.
6. T F Sample sizes of 4 or 5 can be used when building x-bar and R-control charts.
7. T F If we are attempting to control the diameter of bowling balls, we will find a p-chart to be quite helpful.
8. T F A ‘c’-chart would be appropriate to monitor the number of weld defects on the steel plates of a ship’s hull.
MULTIPLE CHOICE
9. Bags of pretzels are sampled to ensure proper weight. The overall average for the samples is nine (9) ounces. Each sample contains 25 bags. The standard deviation is estimated to be three (3) ounces. The upper control chart limit (for 99.7% confidence) for the average would be____ounces. a. 9.4 b. 18.0 c. 10.2 d. 7.2 e. 10.8
10. R-charts measure changes in: a. central tendency. b. degree of variation. c. number of defects per production lot. d. natural variations. e. none of the above.
11. Bags of chocolate candy are sampled to ensure proper weight. The overall average for the samples is 36 ounces. Each sample contains twelve bags. The average range is 1.3 ounces. The upper control chart limit for the average would be: a. 36.3458 b. 35.6542 c. 38.3101 d. 36.6279 e. 37.1258
12. Bags of tea are sampled to ensure proper weight. The overall average for the samples is 8 ounces. Each sample contains 10 bags. The average range is 0.1 ounces. What is the lower limit of the average chart? a. 7.9692 b.
1. T F It is impossible to develop a process that has zero variability.
2. T F Assignable variations in a process are also called natural variations.
3. T F An x-bar chart would be appropriate to monitor the number of defects in a production lot.
4. T F The central limit theorem provides the statistical foundation for control charts.
5. T F If we are tracking quality of performance for a class of students, we should plot the pass/fail result on a p-chart.
6. T F Sample sizes of 4 or 5 can be used when building x-bar and R-control charts.
7. T F If we are attempting to control the diameter of bowling balls, we will find a p-chart to be quite helpful.
8. T F A ‘c’-chart would be appropriate to monitor the number of weld defects on the steel plates of a ship’s hull.
MULTIPLE CHOICE
9. Bags of pretzels are sampled to ensure proper weight. The overall average for the samples is nine (9) ounces. Each sample contains 25 bags. The standard deviation is estimated to be three (3) ounces. The upper control chart limit (for 99.7% confidence) for the average would be____ounces. a. 9.4 b. 18.0 c. 10.2 d. 7.2 e. 10.8
10. R-charts measure changes in: a. central tendency. b. degree of variation. c. number of defects per production lot. d. natural variations. e. none of the above.
11. Bags of chocolate candy are sampled to ensure proper weight. The overall average for the samples is 36 ounces. Each sample contains twelve bags. The average range is 1.3 ounces. The upper control chart limit for the average would be: a. 36.3458 b. 35.6542 c. 38.3101 d. 36.6279 e. 37.1258
12. Bags of tea are sampled to ensure proper weight. The overall average for the samples is 8 ounces. Each sample contains 10 bags. The average range is 0.1 ounces. What is the lower limit of the average chart? a. 7.9692 b.