SCMA 331- Exam 2 Chap 6 Supplement (Answered) With Complete solution 2023/2024

SCMA 331- Exam 2 Chap 6 Supplement
(Answered) With Complete solution 2023/2024
Some degree of variability is present in almost all processes.
True
The purpose of process control is to detect when natural causes of variation are
present.
False
A normal distribution is generally described by its two parameters: the mean and
the range.
False
A process is said to be in statistical control when assignable causes are the only
sources of variation.
False
Mistakes stemming from workers' inadequate training represent an assignable
cause of variation.
True
Averages of small samples, not individual measurements, are generally used in
statistical process control.
True
The x-bar chart indicates that a gain or loss of uniformity has occurred in
dispersion of a production process.
False
The Central Limit Theorem states that when the sample size increases, the
distribution of the sample means will approach the normal distribution.
True
In statistical process control, the range is often used as a substitute for the
standard deviation.
True
If the process average is in control, then the process range must also be in
control.
False
A process range chart illustrates the amount of dispersion within the samples.
True
Mean charts and range charts complement one another, one detecting shifts in
process average, the other detecting shifts in process dispersion.
True
An x-bar chart is used when we are sampling attributes.
False
To measure the voltage of batteries, one would sample by attributes.
False
A p-chart is appropriate to plot the number of typographic errors per page of text.
False
A c-chart is appropriate to plot the number of flaws in a bolt of fabric.

, True
The x-bar chart, like the c-chart, is based on the exponential distribution.
False
If a sample of items is taken and the mean of the sample is outside the control
limits, the process is:

A) likely out of control and the cause should be investigated.

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.
A) likely out of control and the cause should be investigated.
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.
D) natural causes and assignable causes.
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.
E) All of the above are true.
Natural variations:
A) are variations that are to be identified and investigated.
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.
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 investigated.
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.
B) is to be identified and investigated.