A trucking firm suspects that the mean life of a certain tire it uses 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 34,350 miles with a standard
deviation of 1200 miles. At α $\alpha$ = 0.05, test the trucking firmʹs claim.

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The Answer of A trucking firm suspects that the mean life of a certain tire it uses 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 34,350 miles with a standard
deviation of 1200 miles. At α $\alpha$ = 0.05, test the trucking firmʹs claim.

A Trucking Firm Suspects That the Mean Life of a Certain