Question

A shipping firm suspects that the mean life of a certain brand of tire used by its trucks is less than 35,000 miles. To check the claim, the firm randomly selects and tests 18 of these tires and gets a mean lifetime of 34,200 miles with a standard deviation of 1200 miles. At α = 0.05, test the shipping firm's claim. Use the critical value method.

Initial Claim:

Null Hypothesis:

Alternative Hypothesis

Test statistic (make sure you state which test statistic that you are using):

Critical Value

Initial conclusion (justify your answer – graphs are acceptable):

Final Conclusion:

Answer 1