Question

Based on interviews with 92 SARS patients, researchers found that the mean incubation period was 4.5 days, with a standard deviation of 14.2 days. Based on this information, construct a 95% confidence interval for the mean incubation period of the SARS virus. Interpret the interval. The lower bound is days. (Round to two decimal places as needed.)

A. The lower and upper bound is?

B. Interpret the interval.

Answer 1

A. z value for 95% CI is 1.96 as P(-1.96<z<1.96)=0.95

So Margin of Error is $E=z*\frac{s}{\sqrt{n}}=1.96*\frac{14.2}{\sqrt{92}}=2.90$

Hence CI is $\overline{x}\pm E=4.5\pm 2.90=(1.60, 7.40)$

B. Population mean incubation period will lie in the range of 1.60 to 7.40