Question 1

A process that exhibits random variability would be judged to be out of control.

Accepted Answer

A) True 
 B)False

Question 2

Low-cost, high-volume items often require more intensive inspection than other types of items.

Accepted Answer

A) True 
 B)False

Question 3

A quality analyst wants to construct a control chart for determining whether three machines, all producing the same product, are in control with regard to a particular quality variable. Accordingly, he sampled four units of output from each machine, with the following results: $$\begin{array} { c c c c c } 
\text { Machine } &&{ \text { Measurements } } \
\hline \# 1 & 17 & 15 & 15 & 17 \
\# 2 & 16 & 25 & 18 & 25 \
\# 3 & 23 & 24 & 23 & 22
\end{array}$$
What is the estimate of the mean of the sampling distribution for the sample mean?

Accepted Answer

A)  16 
B)  19 
C)  20 
D)  21 
E)  23 
A)  16 
B)  19 
C)  20 
D)  21 
E)  23

Question 4

A plot below the lower control limit on the range chart:
(I) should be ignored since lower variation is desirable.
(II) may be an indication that process variation has decreased.
(III) should be investigated for assignable cause.

Accepted Answer

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

Question 5

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 in 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: $$\begin{array} { l l c c c } 
\text { Day } && { \text { Weight (ounces) } } \
\hline \text { Monday } & 23 & 22 & 23 & 24 \
\text { Tuesday } & 23 & 21 & 19 & 21 \
\text { Wednesday } & 20 & 19 & 20 & 21 \
\text { Thursday } & 18 & 19 & 20 & 19 \
\text { Friday } & 18 & 20 & 22 & 20
\end{array}$$
What is the standard deviation of the sampling distribution of sample means for whenever this process is in 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 6

The amount of inspection we choose can range from no inspection at all to inspecting each item numerous times.

Accepted Answer

A) True 
 B)False

Question 7

Studies on a bottle-filling machine indicate that it fills bottles to a mean of 16 ounces with a standard deviation of 0.10 ounces. What is the process specification, assuming the Cpk index of 1?

Accepted Answer

A)  lower spec = 0.1 ounces and upper spec = 1 ounce 
B)  lower spec = 14.3 ounces and upper spec = 17.7 ounces 
C)  lower spec = 12.0 ounces and upper spec = 21.4 ounces 
D)  lower spec = 15.7 ounces and upper spec = 16.3 ounces 
E)  There is insufficient information to determine the process specification. 
A)  lower spec = 0.1 ounces and upper spec = 1 ounce 
B)  lower spec = 14.3 ounces and upper spec = 17.7 ounces 
C)  lower spec = 12.0 ounces and upper spec = 21.4 ounces 
D)  lower spec = 15.7 ounces and upper spec = 16.3 ounces 
E)  There is insufficient information to determine the process specification.

Question 8

A quality analyst wants to construct a control chart for determining whether three machines, all producing the same product, are in control with regard to a particular quality variable. Accordingly, he sampled four units of output from each machine, with the following results: $$\begin{array} { c c c c c } 
\text { Machine } &&{ \text { Measurements } } \
\hline \# 1 & 17 & 15 & 15 & 17 \
\# 2 & 16 & 25 & 18 & 25 \
\# 3 & 23 & 24 & 23 & 22
\end{array}$$
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?

Accepted Answer

A)  machine #1 
B)  machine #2 
C)  machine #3 
D)  all of the machines 
E)  none of the machines 
A)  machine #1 
B)  machine #2 
C)  machine #3 
D)  all of the machines 
E)  none of the machines

Question 9

The basis for a statistical process control chart is a(the):

Accepted Answer

A)  process capability. 
B)  sampling distribution. 
C)  control limit. 
D)  sample range. 
E)  sample mean. 
A)  process capability. 
B)  sampling distribution. 
C)  control limit. 
D)  sample range. 
E)  sample mean.

Question 10

The process capability index (Cpk) may mislead if:
(I) the process is not stable.
(II) the process output is not normally distributed.
(III) the process is not centered.

Accepted Answer

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

Question 11

The traditional view is that the optimum level of inspection minimizes the sum of inspection costs and the cost of passing defectives.

Accepted Answer

A) True 
 B)False

Question 12

Process capability compares process variability to the tolerances.

Accepted Answer

A) True 
 B)False

Question 13

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 in 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: $$\begin{array} { l r } 
\text { Instructor } & \text { Number of Failures } \
\hline \text { Prof. A } & 13 \
\text { Prof. B } & 0 \
\text { Prof. C } & 11 \
\text { Prof. D } & 16
\end{array}$$
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 14

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 when this service life is in control it 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: $$\begin{array} { c c c c c } 
\text { Sample } & & { \text { Service Life (hours) } } \
\hline 1 & 495 & 500 & 505 & 500 \
2 & 525 & 515 & 505 & 515 \
3 & 470 & 480 & 460 & 470
\end{array}$$
What is the mean of the sampling distribution of sample means when the service life is in control?

Accepted Answer

A)  250 hours 
B)  470 hours 
C)  495 hours 
D)  500 hours 
E)  515 hours 
A)  250 hours 
B)  470 hours 
C)  495 hours 
D)  500 hours 
E)  515 hours

Question 15

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 in 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 are the .95 (5 percent risk of Type I error) upper and lower control limits for the p-chart?

Accepted Answer

A)  .95 and .05 
B)  .13 and .07 
C)  .1588 and .0412 
D)  .16 and .04 
E)  .1774 and .0226 
A)  .95 and .05 
B)  .13 and .07 
C)  .1588 and .0412 
D)  .16 and .04 
E)  .1774 and .0226

Question 16

The variation of a sampling distribution is less than the variation of the underlying process distribution.

Accepted Answer

A) True 
 B)False

Question 17

The sampling distribution can be assumed to be approximately normal even when the underlying process distribution is not normally distributed.

Accepted Answer

A) True 
 B)False

Question 18

Control limits used on process control charts are specifications established by design or customers.

Accepted Answer

A) True 
 B)False

Question 19

Range control charts are used to monitor process central tendency.

Accepted Answer

A) True 
 B)False

Question 20

The following data occurs chronologically from left to right: $$\begin{array} { | l | l | l | l | l | l | } 
\hline 15.2 & 19.7 & 16.0 & 11.1 & 14.8 & 14.5 \
\hline
\end{array}$$
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.

A process that exhibits random variability would be judged to be out of control.

Low-cost, high-volume items often require more intensive inspection than other types of items.

A plot below the lower control limit on the range chart: (I) should be ignored since lower variation is desirable. (II) may be an indication that process variation has decreased. (III) should be investigated for assignable cause.

The amount of inspection we choose can range from no inspection at all to inspecting each item numerous times.

Studies on a bottle-filling machine indicate that it fills bottles to a mean of 16 ounces with a standard deviation of 0.10 ounces. What is the process specification, assuming the Cpk index of 1?

The basis for a statistical process control chart is a(the):

The process capability index (Cpk) may mislead if: (I) the process is not stable. (II) the process output is not normally distributed. (III) the process is not centered.

The traditional view is that the optimum level of inspection minimizes the sum of inspection costs and the cost of passing defectives.

Process capability compares process variability to the tolerances.

The variation of a sampling distribution is less than the variation of the underlying process distribution.

The sampling distribution can be assumed to be approximately normal even when the underlying process distribution is not normally distributed.

Control limits used on process control charts are specifications established by design or customers.

Range control charts are used to monitor process central tendency.

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:

Introduction to Operations Management

Competitiveness

Forecasting

Product and Service Design

RELIABILITY – Static

Strategic Capacity Planning for Products and Services

Decision Theory– Static

Process Selection and Facility Layout

Work Design and Measurement

learning curve– Static

Location Planning and Analysis

The Transportation Model– Static

Management of Quality

Acceptance Sampling– Static

Aggregate Planning and Master Scheduling

MRP and ERP

Inventory Management

JIT and Lean Operations

Maintenance– Static

Supply Chain Management

Scheduling

Project Management

Management of Waiting Lines

Linear Programming

Filters

Exam 14: Quality Control

A process that exhibits random variability would be judged to be out of control.

Low-cost, high-volume items often require more intensive inspection than other types of items.

A plot below the lower control limit on the range chart: (I) should be ignored since lower variation is desirable. (II) may be an indication that process variation has decreased. (III) should be investigated for assignable cause.

The amount of inspection we choose can range from no inspection at all to inspecting each item numerous times.

Studies on a bottle-filling machine indicate that it fills bottles to a mean of 16 ounces with a standard deviation of 0.10 ounces. What is the process specification, assuming the Cpk index of 1?

The basis for a statistical process control chart is a(the):

The process capability index (Cpk) may mislead if: (I) the process is not stable. (II) the process output is not normally distributed. (III) the process is not centered.

The traditional view is that the optimum level of inspection minimizes the sum of inspection costs and the cost of passing defectives.

Process capability compares process variability to the tolerances.

The variation of a sampling distribution is less than the variation of the underlying process distribution.

The sampling distribution can be assumed to be approximately normal even when the underlying process distribution is not normally distributed.

Control limits used on process control charts are specifications established by design or customers.

Range control charts are used to monitor process central tendency.

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:

Introduction to Operations Management

Competitiveness

Forecasting

Product and Service Design

RELIABILITY – Static

Strategic Capacity Planning for Products and Services

Decision Theory– Static

Process Selection and Facility Layout

Work Design and Measurement

learning curve– Static

Location Planning and Analysis

The Transportation Model– Static

Management of Quality

Acceptance Sampling– Static

Aggregate Planning and Master Scheduling

MRP and ERP

Inventory Management

JIT and Lean Operations

Maintenance– Static

Supply Chain Management

Scheduling

Project Management

Management of Waiting Lines

Linear Programming

Filters