Concept explainers
(a)
Interpretation:
The place of indicating control limits on a mean chart by using the sampling procedure that produced the data.
Concept Introduction:
Control limits are the lines which define whether a process is out of control or not. These are the horizontal line which comes above and below the central line.
(a)
Explanation of Solution
Given information:
The data is given as below.
Sample | Sample mean | Sample range |
First, calculate the average of the sample mean.
Then calculate the average of the range.
Find the value of
Then,
Calculate the upper control limit by using below formula.
Next, calculate the lower control limit by using below formula.
(b)
Interpretation:
The position to indicate control limits on range chart by using the same sampling procedure that produced the data.
Concept Introduction:
Control limits are the lines which define whether a process is out of control or not. These are the horizontal line which comes above and below the central line.
(b)
Explanation of Solution
Given information:
The data is given as below.
Sample | Sample mean | Sample range |
Find the values of
Then calculate the average of the range.
Now, derive the upper control limit and lower control limit for the rage charts as shown below.
(c)
Interpretation:
Using the control limits in part a and part b, the sample is in control or not.
Concept Introduction:
Control limits are the lines which define whether a process is out of control or not. These are the horizontal line which comes above and below the central line.
(c)
Explanation of Solution
Given information:
The data is given as below.
New sample data are
First, calculate the average of sample mean by using below formula.
Then, calculate the range by using below formula.
In this, the upper control limit
Hence, the process is out of control.
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Chapter 13 Solutions
Practical Operations Management
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