Suppose a study estimated the population mean for a variable of interest using a 99% confidence interval. If the width of the estimated confidence interval (the difference between the upper limit and the lower limit) is 600 and the sample size used in estimating the mean is 1,000, what is the population standard deviation?
A) 26711.14
B) 2451.23
C) 3684.21
D) 5125.11

Question

Quizplus · Accepted Answer

The width of a confidence interval is calculated as 2 * Z * (σ/√n). For a 99% confidence interval, Z is approximately 2.576. Given the width is 600 and n is 1000, solving for σ gives approximately 3684.21.

Suppose a Study Estimated the Population Mean for a Variable