Assignment:
The dataset contained in the problem Excel file gives data on moisture content for specimens of a certain type of fabric.
a. Create an X-bar R chart, using the first 10 subgroups as the base period. Comment on what is shown.
b. What did you assume to construct these control limits (be specific)? Check the assumptions. Given the information in the base period, how comfortable are you with these assumptions?
c. Repeat part a using the 3 additional runs rules; comment on your findings being sure to state what each rule requires.
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subgroup
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obs 1
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obs 2
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obs 3
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obs 4
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obs 5
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1
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12.2
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12.1
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13.3
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13
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13
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2
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12.4
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13.3
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12.8
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12.6
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12.9
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3
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12.9
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12.7
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14.2
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12.5
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12.9
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4
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13.2
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13
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13
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12.6
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13.9
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5
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12.8
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12.3
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12.2
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13.3
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12
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6
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13.9
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13.4
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13.1
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12.4
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13.2
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7
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12.2
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14.4
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12.4
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12.4
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12.5
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8
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12.6
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12.8
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13.5
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13.9
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13.1
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9
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14.6
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13.4
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12.2
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13.7
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12.5
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10
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12.8
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12.3
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12.6
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13.2
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12.8
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11
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12.6
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13.1
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12.7
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13.2
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12.3
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12
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13.5
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12.3
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12.8
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13.1
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12.9
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13
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13.4
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13.3
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12
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12.9
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13.1
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14
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13.5
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12.4
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13
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13.6
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13.4
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15
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12.3
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12.8
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13
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12.8
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13.5
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16
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12.6
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13.4
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12.1
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13.2
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13.3
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17
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12.1
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12.7
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13.4
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13
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13.9
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18
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13
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12.8
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13
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13.3
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13.1
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19
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12.4
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13.2
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13
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14
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13.1
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20
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12.7
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12.4
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12.4
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13.9
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12.8
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21
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12.6
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12.8
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12.7
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13.4
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13
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22
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12.7
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13.4
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12.1
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13.2
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13.3
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Provide complete and step by step solution for the question and show calculations and use formulas.