A car manufacturer claims that the miles per gallon for a certain model has a mean equal to 40.5 miles with a standard deviation equal to 3.5 miles. Use the following data, obtained from a random sample of 15 such cars, to test the hypothesis that the standard deviation differs from 3.5. Use a = 0.05 Assume normality.

a. Solve using the p-value approach.
b. Solve using the classical approach.

Transcribed Image Text:

37.0 38.0 42.5 45.0 34.0 32.0 36.0 35.5 38.0 42.5 40.0 42.5 35.0 30.0 37.5 9 2 2