Question 1

A run test checks a sequence of observations for randomness.

Accepted Answer

A) True 
 B)False  True

Question 2

When a process is not centered, its capability is measured in a slightly different way. The symbol for this case is Cpk.

Accepted Answer

A) True 
 B)False  True

Question 3

The more effective and all-encompassing a firm's quality control and continuous improvement efforts, the less that company will need to rely on:

Accepted Answer

A)  insourcing. 
B)  inspection. 
C)  outsourcing. 
D)  acceptance sampling. 
E)  capability assessment. 
A)  insourcing. 
B)  inspection. 
C)  outsourcing. 
D)  acceptance sampling. 
E)  capability assessment. B

Question 4

Range charts are used mainly with attribute data.

Accepted Answer

A) True 
 B)False

Question 5

A town's department of public works is concerned about adverse public reaction to a sewer project that is currently in progress. Because of this, the commissioner of public works has authorized a weekly survey to be conducted of town residents. Each week, a sample of 100 residents is questioned on their feelings about the project. The results to date are shown below. Analyze these data using control charts that would provide for a 5 percent risk of Type I error. $$\begin{array} { l r r r r r r r r } 
\text { Week } & 1 & 2 & 3 & 4 & 5 & 6 & 7 & 8 \
\hline \text { Number Opposed } & 10 & 8 & 12 & 6 & 4 & 14 & 8 & 10
\end{array}$$

Accepted Answer

The answer of A town's department of public works is...

Question 6

Organizations should work to improve process capability so that quality control efforts can become more:

Accepted Answer

A)  effective. 
B)  efficient. 
C)  necessary. 
D)  unnecessary. 
E)  widespread. 
A)  effective. 
B)  efficient. 
C)  necessary. 
D)  unnecessary. 
E)  widespread.

Question 7

The probability of concluding that assignable variation exists when only random variation is present is:
(I) the probability of a Type I error.
(II) known as the alpha risk.
(III) highly unlikely.
(IV) the sum of probabilities in the two tails of the normal distribution.

Accepted Answer

A)  I and II 
B)  I and IV 
C)  II and III 
D)  I, II, and IV 
E)  I, III, and IV 
A)  I and II 
B)  I and IV 
C)  II and III 
D)  I, II, and IV 
E)  I, III, and IV

Question 8

Range charts and p-charts are both used for variable data.

Accepted Answer

A) True 
 B)False

Question 9

The range chart (R-chart) is most likely to detect a change in:

Accepted Answer

A)  proportion. 
B)  mean. 
C)  number defective. 
D)  variability. 
E)  sample size. 
A)  proportion. 
B)  mean. 
C)  number defective. 
D)  variability. 
E)  sample size.

Question 10

The chair of the operations management department at Quality University wants to construct a p-chart for determining whether the four faculty teaching the basic P/OM course are under control with regard to the number of students who fail the course. Accordingly, he sampled 100 final grades from last year for each instructor, with the following results: $$\begin{array} { l c } 
\text { Instructor } & \text { Number of Failures } \
\hline \text { Prof. A } & 13 \
\text { Prof. B } & 0 \
\text { Prof. C } & 11 \
\text { Prof. D } & 16
\end{array}$$ What is the estimate of the mean proportion of failures for these instructors?

Accepted Answer

A)  .10 
B)  .11 
C)  .13 
D)  .16 
E)  .40 
A)  .10 
B)  .11 
C)  .13 
D)  .16 
E)  .40

Question 11

Given the following process control data for a quality attribute (three samples of size 400 each): $$\begin{array} { l r } 
\text { Sample } & \text { Defectives } \
\hline \# 1 & 36 \
\# 2 & 32 \
\# 3 & 52
\end{array}$$ If the process proportion of defectives is unknown, using .10 alpha risk control limits, do any of the sample proportions indicate an out-of-control process proportion of defectives?

Accepted Answer

The answer of Given the following process control data for...

Question 12

The following data occurs chronologically from left to right: $$\begin{array} { l l l l l l } 
15.2 & 19.7 & 16.0 & 11.1 & 14.8 & 14.5
\end{array}$$ The number of runs up and down is:

Accepted Answer

A)  2. 
B)  3. 
C)  4. 
D)  5. 
E)  none of these. 
A)  2. 
B)  3. 
C)  4. 
D)  5. 
E)  none of these.

Question 13

A p-chart would be used to monitor:

Accepted Answer

A)  average shrinkage. 
B)  dispersion in sample data. 
C)  the fraction defective. 
D)  the number of defects per unit. 
E)  the range of values. 
A)  average shrinkage. 
B)  dispersion in sample data. 
C)  the fraction defective. 
D)  the number of defects per unit. 
E)  the range of values.

Question 14

Range control charts are used to monitor process central tendency.

Accepted Answer

A) True 
 B)False

Question 15

A design engineer wants to construct a sample mean chart for controlling the service life of a halogen headlamp his company produces. He knows from numerous previous samples that this service life is normally distributed with a mean of 500 hours and a standard deviation of 20 hours. On three recent production batches, he tested service life on random samples of four headlamps, with these results: $$\begin{array} { r } 
 { \text { Service Life (hours) } }\
\begin{array} { l l l l l } 
\text { Sample } & \
\hline 1 & 495 & 500 & 505 & 500 \
2 & 525 & 515 & 505 & 515 \
3 & 470 & 480 & 460 & 470
\end{array}\end{array}$$ If he uses upper and lower control limits of 520 and 480 hours, on what sample(s) (if any) does service life appear to be out of control?

Accepted Answer

A)  sample 1 
B)  sample 2 
C)  sample 3 
D)  both samples 2 and 3 
E)  all samples are in control 
A)  sample 1 
B)  sample 2 
C)  sample 3 
D)  both samples 2 and 3 
E)  all samples are in control

Question 16

A quality analyst wants to construct a control chart for determining whether four machines, all producing the same product, are under control with regard to a particular quality attribute. Accordingly, she inspected 1,000 units of output from each machine in random samples, with the following results: $$\begin{array} { l c } 
\text { Machine } & \text { Total Defectives } \
\hline   \# 1 & 23 \
\# 2 & 15 \
\# 3 & 29 \
\# 4 & 13
\end{array}$$ What is the sample proportion of defectives for machine #1?

Accepted Answer

A)  .023 
B)  .02 
C)  .0115 
D)  .0058 
E)  .005 
A)  .023 
B)  .02 
C)  .0115 
D)  .0058 
E)  .005

Question 17

A process that makes chocolate candy bars has an output that is normally distributed with a mean of 6 ounces and a standard deviation of .01 ounces. A job is to be run that requires 200 candy bars. Determine the three-sigma control limits for an x-bar chart, assuming a sample size of 10.
If specifications are 5.98 to 6.02, what run size should be used for this job so that the expected number of good candy bars is 200, assuming the process is in control?

Accepted Answer

The answer of A process that makes chocolate candy bars...

Question 18

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 20 ounces and a standard deviation of two ounces. Each day last week, he randomly selected four packages and weighed each: $$\begin{array} { r } 
{ \text { Weight (ounces) } }\
\begin{array} { l l l l l } 
\text { Day } \
\hline \text { Monday } & 23 & 22 & 23 & 24 \
\text { Tuesday } & 23 & 21 & 19 & 21 \
\text { Wednesday } & 20 & 19 & 20 & 21 \
\text { Thursday } & 18 & 19 & 20 & 19 \
\text { Friday } & 18 & 20 & 22 & 20
\end{array}\end{array}$$ What is the standard deviation of the sampling distribution of sample means for whenever this process is under control?

Accepted Answer

A)  0.1 ounces 
B)  0.4 ounces 
C)  0.5 ounces 
D)  1 ounce 
E)  2 ounces 
A)  0.1 ounces 
B)  0.4 ounces 
C)  0.5 ounces 
D)  1 ounce 
E)  2 ounces

Question 19

When a process is in control, it results in there being, on average, 16 defects per unit of output. c-chart limits of 4 and 28 would lead to a _______ percent chance of a Type I error.

Accepted Answer

A)  67 
B)  92 
C)  33 
D)  0.3 
E)  5 
A)  67 
B)  92 
C)  33 
D)  0.3 
E)  5

Question 20

The primary purpose of statistical process control is to detect a defective product before it is shipped to a customer.

Accepted Answer

A) True 
 B)False

A run test checks a sequence of observations for randomness.

When a process is not centered, its capability is measured in a slightly different way. The symbol for this case is C_pk.

The more effective and all-encompassing a firm's quality control and continuous improvement efforts, the less that company will need to rely on:

Range charts are used mainly with attribute data.

Organizations should work to improve process capability so that quality control efforts can become more:

The probability of concluding that assignable variation exists when only random variation is present is: (I) the probability of a Type I error. (II) known as the alpha risk. (III) highly unlikely. (IV) the sum of probabilities in the two tails of the normal distribution.

Range charts and p-charts are both used for variable data.

The range chart (R-chart) is most likely to detect a change in:

The following data occurs chronologically from left to right: 15.2 19.7 16.0 11.1 14.8 14.5 The number of runs up and down is:

A p-chart would be used to monitor:

Range control charts are used to monitor process central tendency.

When a process is in control, it results in there being, on average, 16 defects per unit of output. c-chart limits of 4 and 28 would lead to a _______ percent chance of a Type I error.

The primary purpose of statistical process control is to detect a defective product before it is shipped to a customer.

Introduction to Operations Management

Competitiveness, Strategy, and Productivity

Forecasting

Product and Service Design

Extension: Reliability

Strategic Capacity Planning for Products and Services

Extension: Decision Theory

Process Selection and Facility Layout

Work Design and Measurement

Extension: Learning Curves

Location Planning and Analysis

Extension: The Transportation Model

Management of Quality

Extension: Acceptance Sampling

Aggregate Planning and Master Scheduling

MRP and ERP

Inventory Management

Jit and Lean Operations

Extension: Maintenance

Supply Chain Management

Scheduling

Project Management

Management of Waiting Lines

Linear Programming

Filters

Exam 10: Quality Control

A run test checks a sequence of observations for randomness.

When a process is not centered, its capability is measured in a slightly different way. The symbol for this case is Cpk.

The more effective and all-encompassing a firm's quality control and continuous improvement efforts, the less that company will need to rely on:

Range charts are used mainly with attribute data.

Organizations should work to improve process capability so that quality control efforts can become more:

The probability of concluding that assignable variation exists when only random variation is present is: (I) the probability of a Type I error. (II) known as the alpha risk. (III) highly unlikely. (IV) the sum of probabilities in the two tails of the normal distribution.

Range charts and p-charts are both used for variable data.

The range chart (R-chart) is most likely to detect a change in:

The following data occurs chronologically from left to right: 15.2 19.7 16.0 11.1 14.8 14.5 The number of runs up and down is:

A p-chart would be used to monitor:

Range control charts are used to monitor process central tendency.

When a process is in control, it results in there being, on average, 16 defects per unit of output. c-chart limits of 4 and 28 would lead to a _______ percent chance of a Type I error.

The primary purpose of statistical process control is to detect a defective product before it is shipped to a customer.

Introduction to Operations Management

Competitiveness, Strategy, and Productivity

Forecasting

Product and Service Design

Extension: Reliability

Strategic Capacity Planning for Products and Services

Extension: Decision Theory

Process Selection and Facility Layout

Work Design and Measurement

Extension: Learning Curves

Location Planning and Analysis

Extension: The Transportation Model

Management of Quality

Extension: Acceptance Sampling

Aggregate Planning and Master Scheduling

MRP and ERP

Inventory Management

Jit and Lean Operations

Extension: Maintenance

Supply Chain Management

Scheduling

Project Management

Management of Waiting Lines

Linear Programming

Filters

When a process is not centered, its capability is measured in a slightly different way. The symbol for this case is C_pk.