Question: 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 39.8 42.3 42.6 41.0 39.8 39.6 38.8
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.