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Use 99% confidence interval to estimate sample size

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General Motors pays for employee education. The HR director would like to conduct a study on the average GPA of employees who have used this benefit to complete their degrees using a sample of education records over the past 10 years. GPA's range between 2.0 and 4.0. The mean GPA is estimated to be plus or minus .05 the population mean. The standard deviation is estimated to be .279. Use the 99% confidence interval to estimate the appropriate sample size needed to do the analysis.

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This solution helps explore how to use confidence intervals to estimate the appropriate sample size needed.

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