Question

To estimate the mean height μ of male students on your campus, you will measure an SRS of students. You know from government data that the standard deviation of the heights of young men is about σ = 2.7 inches. You want your sample mean x to estimate μ with an error of no more than one-half inch in either direction. What standard deviation must x have so that 99.7% of all samples give an x within one-half inch of μ? (Use the 68-95-99.7 rule. Round your answer to four decimal places.) How large an SRS do you need to reduce the standard deviation of x to the value you found in the previous part? (Enter your answer as a whole number.)

Answer 1