Question: An analyst from an energy research institute in California wishes
An analyst from an energy research institute in California wishes to precisely estimate the 99% confidence interval for the average price of unleaded gasoline in the state. In particular, she does not want the sample mean to deviate from the population mean by more than $0.06. What is the minimum number of gas stations that she should include in her sample if she uses the standard deviation estimate of $0.32, as reported in the popular press?
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