Manufacturing and Product Development
Nitterhouse Masonry Products, LLC, in Chambersburg, Pennsylvania, produces architectural concrete masonry products. The Dover is the largest block in a certain collection, is used primarily for residential retaining walls, and is manufactured to weigh 40 pounds. A quality control inspector for the company randomly selected eight blocks, and the weight (in pounds) of each is given in the following table.
|
43.4
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39.8
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42.3
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42.6
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41.0
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39.8
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39.6
|
38.8
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Assume the underlying population is normal and σ = 2 pounds. Is there any evidence to suggest that the true mean weight of the blocks is different from 40 pounds? Use a = 0.05 and compute the p value to draw a conclusion.