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In: Statistics and Probability

The mean and standard deviation of a random sample of n measurements are equal to 33.2...

The mean and standard deviation of a random sample of n measurements are equal to 33.2 and 3.6?, respectively.

a. Find a 90?% confidence interval for mu if nequals81.

b. Find a 90?% confidence interval for mu if nequals324.

c. Find the widths of the confidence intervals found in parts a and b. What is the effect on the width of a confidence interval of quadrupling the sample size while holding the confidence coefficient? fixed?

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