How big of a sample would be needed to get a confidence interval for the mean distance commuted by the population of all commuters with a margin of error of 2 miles, and a confidence level of 99%, if the population standard deviation is 3 miles, as above?
3.) How big of a sample would be needed to get a confidence interval for the mean distance commuted by the population of all commuters with a margin of error of 2 miles, and a confidence level of 99%, if the population standard deviation is 3 miles, as above?
4.) The mean length of a sample of 41 fish of a particular species is 21 inches, and the standard deviation of the lengths of the fish in the sample is 2 inches. For a 95% confidence level,
a. What kind of confidence interval should we do (z or t) and why?
b. Find the confidence interval for the mean length of all of the fish of this species.
c. For a
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