IQ tests are designed to yield results that are approximatelyNormally distributed. Researchers think believe that the standarddeviation, σ, is 15. A reporter is interested in estimating theaverage IQ of employees in a large high-tech firm in California.She gathers the IQ information on 22 employees of this firm andrecoreds the sample mean IQ as 106. Let X represent a randomvariable describing a person's IQ: X~N(µ, 15).
a. Find the standard error of the sample mean.
b. Calculate a 90% confidence interval.
c. Interpret the confidence interval in the context of theproblem.
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