You want to obtain a sample to estimate a population mean. Based on previous evidence, you believe the population standard deviation is approximately σ=38.9σ=38.9. You would like to be 99% confident that your estimate is within 1 of the true population mean. How large of a sample size is required? n =  Do not round mid-calculation. However, you are encouraged to use a critical value accurate to three decimal places — this is important for the system to be able to give hints for incorrect answers.

You want to obtain a sample to estimate a population mean. Based on previous evidence, you believe the population standard deviation is approximately σ=38.9σ=38.9. You would like to be 99% confident that your estimate is within 1 of the true population mean. How large of a sample size is required?

n = 



Do not round mid-calculation. However, you are encouraged to use a critical value accurate to three decimal places — this is important for the system to be able to give hints for incorrect answers.