According to R.L. Polk & Company, the median age of automobiles and trucks on the road in the United States is about 9 years. The ages for a random sample of vehicles in the executive parking lot of a metal fabrication company are listed in file XR14059. Using the sign test and the 0.05 level of significance, examine whether the median age for cars driven to work by the company’s executives might be less than the median reported by R.L. Polk. Identify and interpret the p-value for the test.
A computer and statistical software.