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Confidence Interval using Z test for mean and proportion.

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See attached data file.

Using the cumba file attached complete the following problems:

Using the age data only. conduct a 95% confidence interval of the mean age of employees at Cumba Inc.

Using the gender data only, conduct a 95% confidence interval of the proportion of female employees at cimab Inc.

In one or two sentences interpret the results.

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This solution is comprised of a detailed explanation of confidence interval for mean and proportions using the Z test. In this solution, step-by-step explanation of this complicated topic provides students with a clear perspective of confidence interval for mean and proportions using the Z test. Excel is used for calculations.

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