Test Hypotheses About a Population Mean with Known Using the Classical

Short Answer

Test Hypotheses about a Population Mean with Known Using the Classical Approach
-A shipping firm suspects that the mean lifetime of the tires used by its trucks is less than 40,000 miles. To check the claim, the firm randomly selects and tests 54 of these tires and gets a mean lifetime of 39,370 miles with a standard deviation of 1200 miles. At $\alpha = 0.05$ , test the shipping firm's claim.