in its auto reliability survey, consumer reports asked subscribers to report their maintenance and repair costs. most individuals are aware of the fact that the average annual repair cost for an automobile depends on the age of the automobile. a researcher is interested in finding out whether the variance of the annual repair costs also increases with the age of the automobile. a sample of automobiles years old showed a sample standard deviation for annual repair costs of and a sample of automobiles years old showed a sample standard deviation for annual repair costs of .