Suppose the speeds of vehicles traveling on a highway are normally distributed and have a known population standard deviation of 7 miles per hour and an unknown population mean. A random sample of 32 vehicles is taken and gives a sample mean of 64 miles per hour. Find the margin of error for the confidence interval for the population mean with a 98% confidence level. z0.10 z0.05 z0.025 z0.01 z0.005 1.282 1.645 1.960 2.326 2.576 You may use a calculator or the common z values above. • Round the final answer to two decimal places. Provide your answer below:
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Looking at the provided z-scores, we see that the closest one to 98% is Z0.01 = 2.326 (which actually corresponds to a 99% confidence level, but it's the closest one we have). Show more…
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