Question: A certain vehicle emission inspection station advertises that the wait
A certain vehicle emission inspection station advertises that the wait time for customers is less than 8 minutes. A local resident is skeptical and collects a random sample of 49 wait times for customers at the testing station. He ﬁnds that the sample mean is 7.34 minutes, with a standard deviation of 3.2 minutes. Does the sample evidence support the resident’s skepticism? Use the α = 0.01 level of signiﬁcance.
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