Chapter 15 Statistical Quality Control

Table 15-1

Sample Size n	Mean Factor A2	Upper Range D4	Lower Range D3
2	1.880	3.628	0
3	1.023	2.574	0
4	0.729	2.282	0
5	0.577	2.114	0
6	0.483	2.004	0
7	0.419	1.924	0.076
8	0.373	1.864	0.136
9	0.337	1.816	0.184
10	0.308	1.777	0.223
12	0.266	1.716	0.284

30) Refer to Table 15-1. 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 sample averages would be

A) 36.3458.

B) 35.6542.

C) 38.3101.

D) 36.6279.

E) 37.1258.

31) Refer to Table 15-1. Bags of chocolate candy are sampled to ensure proper weight. The overall average for the samples is 36 ounces. Each sample contains eight bags. The average range is 1.3 ounces. The lower control chart limit for the sample averages would be

A) 36.3730.

B) 36.4849.

C) 35.6270.

D) 35.5150.

E) None of the above

32) Refer to Table 15-1. To guarantee that cans of soup are properly filled, some cans are sampled and the amounts measured. The overall average for the samples is 12 ounces. Each sample contains 10 cans. The average range is 0.4 ounces. The upper control chart limit for the sample averages would be

A) 12.1232.

B) 11.8768.

C) 13.2.

D) 12.308.

E) None of the above

33) Refer to Table 15-1. To guarantee that cans of soda are properly filled, some cans are sampled and the amounts measured. The overall average for the samples is 12 ounces. Each sample contains 10 cans. The average range is 0.4 ounces. The lower control chart limit for the sample averages would be

A) 12.1232.

B) 11.8768.

C) 13.2.

D) 12.308.

E) None of the above

34) Refer to Table 15-1. 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 sample averages chart?

A) 7.9692

B) 8.0308

C) 7.9076

D) 8.0924

E) None of the above

35) Refer to Table 15-1. The Pristine Paint Company produces paint in gallon cans. They have found that in more than 10 samples of 8 cans each, the average gallon can contains 1.1 gallons of paint. The average range found over these samples is 0.15 gallons. What is the upper control limit for the sample averages in this process?

A) 1.100

B) 1.150

C) 1.268

D) 1.156

E) None of the above

36) Refer to Table 15-1. The average range of a process for packaging cereal is 1.1 ounces. If the sample size is 10, find the upper control chart limit for the range chart.

A) 0.245

B) 1.955

C) 1.777

D) 0.223

E) None of the above

37) Refer to Table 15-1. The average range of a process for packaging cereal is 1.1 ounces. If the sample size is 10, find the lower control chart limit for the range chart.

A) 0.245

B) 1.955

C) 1.777

D) 0.223

E) None of the above

38) The U.S. government award for quality achievement is the

A) Deming Prize.

B) Shewhart Symbol of Excellence.

C) Malcolm Baldrige National Quality Award.

D) Bush Award for Quality Management.

E) Six Sigma Certification.

39) The p-chart would be useful when we

A) took a number of measurements and computed the average.

B) took a number of measurements and computed the ranges.

C) found the fraction of the production lot defective.

D) found the number of defective items in a production lot.

E) None of the above

40) A p-chart is based on which of the following probability distributions?

A) Poisson

B) Binomial

C) Uniform

D) Exponential

E) Gamma

41) A c-chart is based on which of the following probability distributions?

A) Poisson

B) Binomial

C) Uniform

D) Exponential

E) Gamma

42) Which of the following statements is FALSE regarding control charts?

A) X-bar charts measure central tendency in a process.

B) R-charts measure the variability of a process.

C) It is not possible to have a LCL below 0 in a c-chart.

D) It is not possible to have a UCL value above 1 in a p-chart.

E) The nominal line is always the midpoint between the UCL and LCL.