Answer:
See explaination
Step-by-step explanation:
Refer to attached file for table used in solving mean.
The mean of range is
\bar{R}=\frac{13.3}{20}=0.665
The mean of all six means:
\bar{\bar{x}}=\frac{1907.96}{20}=95.398
(a)
Here sungroup size is 5:
Range chart:
From constant table we have
D_{4}=2.114
So upper control limit:
UCL_{R}=D_{4}\cdot \bar{R}=2.114\cdot 0.665=1.40581
Lower control limit:
LCL_{R}=0.0000
Central limit: \bar{R}=0.665
Since all the range points are with in control limits so this chart shows that process is under control.
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X-bar chart:
From constant table we have
A_{2}=0.577
So upper control limit:
UCL_{\bar{x}}=\bar{\bar{x}}+A_{2}\cdot \bar{R}=95.398+0.577\cdot 0.665=95.78
Lower control limit:
LCL_{\bar{x}}=\bar{\bar{x}}-A_{2}\cdot \bar{R}=95.398-0.577\cdot 0.665=95.01
Central limit: \bar{\bar{x}}=95.398
Sample number 94.82 is not in teh limits of x-bar chart so it seems that process is not in control
