An economist is interested in studying the incomes of consumers in a particular region. The economist needs to know how large a sample should be taken so that a 90% confidence interval for their mean income with an error of $500 can be constructed. If the population standard deviation is known to be $8,000 what sample size would the economist need to use?
- Sample Size = 693
- Sample Size = 984
- Sample Size = 112
- Sample Size = 576