Question: The Stewart aviation products company uses a new production method to manufacture aircraft altimeters. A simple random sample of 81 altimeters is tested in a pressure chamber, & the errors in altitude are recorded as positive values [for readings that are too high] & negative values [for readings that are too low]. The sample has a standard deviation of s=52.3 feet
At the .05 significance level, test the claim that the new production line has errors with a standard deviation different from 43.7 feet. which was the standard deviation for the old production method. Suppose that the sample is drawn from a normally distributed population.