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Sample size Determination - standard deviation

27. Annual starting salaries for college graduates with degrees in business administration are generally expected to be between $30,000 and $45,000. Assume that a 95% confidence interval estimate of the population mean annual starting salary is desired. What is the planning value for the population standard deviation? How large a sample should be taken if the desired margin of error is

a. $500?

b. $200?

c. $100?

d. Would you recommend trying to obtain the $100 margin or error?

Solution Preview

The planning value for the population standard deviation is given by,
= (45000 – 30000)/4 = 3750.
We have, the sample size formula,
For 95% confidence level, = 1.96.
a) The ...

Solution Summary

The solution illustrates the method of determination of Sample size.