Academic Integrity: tutoring, explanations, and feedback — we don’t complete graded work or submit on a student’s behalf.

An analyst from an energy research institute in California wishes to precisely e

ID: 3384736 • Letter: A

Question

An analyst from an energy research institute in California wishes to precisely estimate a 93% 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 $0.07. What is the minimum number of gas stations that she should include in her sample if she uses the standard deviation estimate of $0.22, as reported in the popular press? Use Table 1. (Do not round intermediate calculations. Round "z" value to 2 decimal places. Round up your answer to the nearest whole number.)

An analyst from an energy research institute in California wishes to precisely estimate a 93% 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 $0.07. What is the minimum number of gas stations that she should include in her sample if she uses the standard deviation estimate of $0.22, as reported in the popular press? Use Table 1. (Do not round intermediate calculations. Round "z" value to 2 decimal places. Round up your answer to the nearest whole number.)

Explanation / Answer

An analyst from an energy research institute in California wishes to precisely e