A Quality Analyst wants to construct a sample mean chart for controlling a packaging process. He knows from past experience that whenever this process is under control, package weight is normally distributed with a mean of twenty ounces and a standard deviation of two ounces. Each day last week, he randomly selected four packages and weighed each: Day WEIGHT (ounces)
Monday 23 22 23 24
Tuesday 23 21 19 21
Wednesday 20 19 20 21
Thursday 18 19 20 19
Friday 18 20 22 20
If he uses upper and lower control limits of 22 and 18 ounces, on what day(s), if any, does this process appear to be out of control?
Question 1 options:
Monday
Tuesday
Monday and Tuesday
Monday, Tuesday, and Thursday
none
Save
Question 2 (1.67 points)
A Quality Analyst wants to construct a control chart for determining whether three machines, all producing the same product, are under control with regard to a particular quality variable. Accordingly, he sampled four units of output from each machine, with the following results:
Machine Measurements
Number1 17 15 15 17
Number2 16 25 18 25
Number3 23 24 23 22
For upper and lower control limits of 23.29 and 16.71, which machine(s), if any, appear(s) to have an out-of-control process mean?
Question 2 options:
machine Number1
machine Number2
machine Number3
all of the machines
none of the machines
Save
Question 3 (1.66 points)
A Quality Analyst wants to construct a control chart for determining whether three machines, all producing the same product, are under control with regard to a particular quality variable. Accordingly, he sampled four units of output from each machine, with the following results:
Machine Measurements
Number1 17 15 15 17
Number2 16 25 18 25
Number3 23 24 23 22
What is the estimate of the process mean for whenever it is under control?
Question 3 options:
16
19
20
21
23
Save
Question 4 (2.5 points)
Specifications for a piece of material used in the manufacture of a bed mattress require that the piece be between 52.47 and 55.53 inches. The process that produces the piece yields a mean of 54 and a standard deviation of 0.9 inches. The distribution of output is normal. What percentage of the pieces will meet the length specs?
Question 4 options:
4.45 %
91.08 %
97.85 %
95.54 %
None of the Above
Save
Question 5 (2.5 points)
Specifications for a piece of material used in the manufacture of a bed mattress require that the piece be between a Lower and Upper value (in inches) centered around the process mean. The process that produces the piece yields a mean of 59 and a standard deviation of 0.8 inches. The distribution of output is normal. Within what values will 85.01 percent of sample means fall, if samples of n = 5 are taken and the process is in control?
Question 5 options:
58.484 , 59.515
58.166 , 59.833
57.847 , 60.152
57.211 , 60.788
None of the Above
Save
Question 6 (2.5 points)
Loan Processing times are being monitored at a local company. Samples of six observations each have been taken, and the results are listed. Using Factors from Table 10.3, determine lower and upper control limits for a a mean chart
Sample Number 1 2 3 4 5
44 48 56 46 27
32 49 26 52 42
31 31 21 42 40
33 26 35 46 39
41 44 40 27 44
27 43 28 46 36
Question 6 options:
25.664 , 50.468
26.834 , 49.298
10.922 , 65.21
24.494 , 51.638
None of the Above
Save
Question 7 (2.5 points)
Loan Processing times are being monitored at a local company. Samples of ten observations each have been taken, and the results are listed. Using Factors from Table 10.2, determine lower and upper control limits for a a Range chart
Sample Number 1 2 3
79 81 77
72 79 83
74 70 82
82 81 84
69 64 80
82 76 71
82 85 64
90 69 85
76 71 83
72 75 85
Question 7 options:
4.62 , 37.38
2.31 , 45.675
0 , 53.97
64.159 , 90.706
None of the Above
Save
Question 8 (2.5 points)
Using samples of 200 credit card statements, an Auditor found the following:
---Sample Number: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15
Number of Errors: 27 23 23 28 22 25 35 33 27 27 34 27 33 21 25
Determine lower and upper control limits for the fraction of errors using three-sigma limits.
Question 8 options:
.075 , .197
.088 , .185
.063 , .209
.039 , .233
None of the Above
Save
Question 9
The Quality Control Manager at a Credit Card Collection Center is concerned about how many complaints the company is getting from customers. The following data were collected for 15 days of operation:
Sample Number: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15
Number of Complaints: 15 1 23 2 2 13 21 4 9 14 7 22 10 2 18
Determine lower and upper control limits for the number of complaints they should expect each day using three-sigma limits.
Question 9 options:
2.625 , 19.107
.977 , 20.756
0 , 24.052
4.273 , 17.459
None of the Above