Question 6.129

6.129 Using software with summary measures.

Most statistical software packages provide an option of find confidence interval limits by inputting the sample mean, sample size, population standard deviation, and desired confidence level.

  • JMP users: Do the following pull-down sequence: Help → Sample Data and then select Confidence Interval for One Mean found in the Calculators group.
  • Minitab users: Do the following pull-down sequence: Stat → Basic Statistics → 1 Sample Z and select Summarized data option.
  1. Have software find the 95% confidence interval for the mean when , , and .
  2. Find a 93.5% confidence interval using the information of part (a).

6.129

(a) (18.49, 21.51). (b) (18.58, 21.42)