The Stewart Aviation Products Company uses a new production method to manufacture aircraft altimeters. A random sample of 81 altimeters resulted in errors with a standard deviation of s = 52.3 ft. At the 0.05 level of significance, test the claim that the new production line has errors with a standard deviation different from 43.7 ft, which was the standard deviation for the old production method. If it appears that the standard deviation has changed, does the new production method appear to be better or worse than the old method?
Use the traditional method to test the given hypotheses. Follow the steps outlined and draw the appropriate graph. In all cases, assume that the population is normally distributed and that the sample has been randomly selected.