A well-known automotive magazine took three top of the line mid size automobiles manufactured in the United States, test-drove them, and compared them on a variety of criteria. In the area of gasoline mileage performance, five automobiles of each brand were each test-driven 500 miles; the miles per gallon data obtained follow. Use a=.05 to test whether there is significant difference in the mean number of miles per gallon for the three types of automobiles.
See attachment for table.
The expert uses an ANOVA table to compare mid size automobiles in the United States. The criteria that was compared was the area of gasoline mileage performance and the miles per gallon. Each automobile were test drove for 500 miles.