The manufacturer of the X-15 steel-belted radial truck tire claims that the mean mileage the tire can be driven before the tread wears out is 60,000 miles. The population standard deviation of the mileage is 5,000 miles. Crosset Truck Company bought 48 tires and found that the mean mileage for its trucks is 59,500 miles.
A. State the null hypothesis and the alternate hypothesis.
B. Compute the value of the test statistic.
C. What is the p-value?