An auto maker claims that the mean gas mileage of its luxury sedan is at least...

An auto maker claims that the mean gas mileage of its luxury sedan is at least 25 miles per gallon. A random sample of 36 such cars were tested and resulted in a sample mean of 24.2 miles per gallon and a sample standard deviation of 2.8 miles per gallon. At α = 0.05, is there sufficient evidence to reject the auto maker’s claim?

Claim:

H0:

H1:

Test Statistic:

Critical Region/Critical Value:

Decision about H0:

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Expert Solution

orchestra answered 2 years ago

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