ISDS 3115 Test 2 Version 1
Exam Study Guide – Practice
Questions with Verified
Answers. GRADED A+. Latest
2026/2027 Update
Natural variations
a. affect almost every production process
b. are the many sources of variation that occur when a process is under control
c. when grouped, form a pattern, or distribution
d. are tolerated, within limits, when a process is under control
e. All of the above are true. - Answer✔✔-e. All of the above are true.
Natural variations
a. are variations that are to be identified and eliminated
,b. are variations that can be traced to a specific cause
c. are the same as assignable variations
d. lead to occasional false findings that processes are out of control
e. play no role in statistical process control- Answer✔✔-d. lead to occasional false
findings that processes are out of control
Assignable variation
a. is a sign that a process is under control
b. is to be identified and eliminated
c. is the same as random variation
d. is variation that cannot be traced to a specific cause
e. leads to a steep OC curve - Answer✔✔-b. is to be identified and eliminated
Assignable causes
a. are not as important as natural causes
b. are within the limits of a control chart
c. depend on the inspector assigned to the job
d. are also referred to as "chance" causes
e. are causes of variation that can be identified and removed - Answer✔✔-e. are
causes of variation that can be identified and removed
If a sample of items is taken and the mean of the sample is outside the control
limits the process is
,a. out of control and the cause should be established
b. in control, but not capable of producing within the established control limits
c. within the established control limits with only natural causes of variation
d. monitored closely to see if the next sample mean will also fall outside the
control limits
e. producing high quality products - Answer✔✔-a. out of control and the cause
should be established
The causes of variation in statistical process control are
a. cycles, trends, seasonality, and random variations
b. producer's causes and consumer's causes
c. mean and range
d. natural causes and assignable causes
e. Type I and Type II - Answer✔✔-d. natural causes and assignable causes
Control charts for variables are based on data that come from
a. acceptance sampling
b. individual items
c. averages of small samples
d. averages of large samples
, e. the entire lot - Answer✔✔-c. averages of small samples
The purpose of an X chart is to determine whether there has been a
a. gain or loss in uniformity
b. change in the percent defective in a sample
c. change in the central tendency of the process output
d. change in the number of defects in a sample
e. change in the AOQ - Answer✔✔-c. change in the central tendency of the
process output
Statistical process control charts
a. display the measurements on every item being produced
b. display upper and lower limits for process variables or attributes, and signal
when a process is no longer in control
c. indicate to the process operator the average outgoing quality of each lot
d. indicate to the operator the true quality of material leaving the process
e. none of the above - Answer✔✔-b. display upper and lower limits for process
variables or attributes, and signal when a process is no longer in control
A sample of parts is measured. The mean of this sample is in the middle of the
control limits, but some individual parts measure too low for design specifications
and other parts measure too high.
Exam Study Guide – Practice
Questions with Verified
Answers. GRADED A+. Latest
2026/2027 Update
Natural variations
a. affect almost every production process
b. are the many sources of variation that occur when a process is under control
c. when grouped, form a pattern, or distribution
d. are tolerated, within limits, when a process is under control
e. All of the above are true. - Answer✔✔-e. All of the above are true.
Natural variations
a. are variations that are to be identified and eliminated
,b. are variations that can be traced to a specific cause
c. are the same as assignable variations
d. lead to occasional false findings that processes are out of control
e. play no role in statistical process control- Answer✔✔-d. lead to occasional false
findings that processes are out of control
Assignable variation
a. is a sign that a process is under control
b. is to be identified and eliminated
c. is the same as random variation
d. is variation that cannot be traced to a specific cause
e. leads to a steep OC curve - Answer✔✔-b. is to be identified and eliminated
Assignable causes
a. are not as important as natural causes
b. are within the limits of a control chart
c. depend on the inspector assigned to the job
d. are also referred to as "chance" causes
e. are causes of variation that can be identified and removed - Answer✔✔-e. are
causes of variation that can be identified and removed
If a sample of items is taken and the mean of the sample is outside the control
limits the process is
,a. out of control and the cause should be established
b. in control, but not capable of producing within the established control limits
c. within the established control limits with only natural causes of variation
d. monitored closely to see if the next sample mean will also fall outside the
control limits
e. producing high quality products - Answer✔✔-a. out of control and the cause
should be established
The causes of variation in statistical process control are
a. cycles, trends, seasonality, and random variations
b. producer's causes and consumer's causes
c. mean and range
d. natural causes and assignable causes
e. Type I and Type II - Answer✔✔-d. natural causes and assignable causes
Control charts for variables are based on data that come from
a. acceptance sampling
b. individual items
c. averages of small samples
d. averages of large samples
, e. the entire lot - Answer✔✔-c. averages of small samples
The purpose of an X chart is to determine whether there has been a
a. gain or loss in uniformity
b. change in the percent defective in a sample
c. change in the central tendency of the process output
d. change in the number of defects in a sample
e. change in the AOQ - Answer✔✔-c. change in the central tendency of the
process output
Statistical process control charts
a. display the measurements on every item being produced
b. display upper and lower limits for process variables or attributes, and signal
when a process is no longer in control
c. indicate to the process operator the average outgoing quality of each lot
d. indicate to the operator the true quality of material leaving the process
e. none of the above - Answer✔✔-b. display upper and lower limits for process
variables or attributes, and signal when a process is no longer in control
A sample of parts is measured. The mean of this sample is in the middle of the
control limits, but some individual parts measure too low for design specifications
and other parts measure too high.
