# Question: A highway patrol officer believes that the average speed of

A highway patrol officer believes that the average speed of cars traveling over a certain stretch of highway exceeds the posted limit of 55 mph. The speeds of a random sample of 200 cars were recorded. Do these data provide sufficient evidence at the 1% significance level to support the officer’s belief? What is the p-value of the test? (Assume that the standard deviation is known to be 5.)

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