For Exercises 65–68, software output from a confidence interval for is provided. For each, examine the indicated software output, and do the following:

  1. Report the confidence interval in the form “(lower bound, upper bound).”
  2. Interpret the confidence interval.
  3. Find the margin of error for the confidence interval.
  4. Interpret the margin of error.

Question 8.67

67. Fourth-Graders' Feet. For the CrunchIt! Output, represents the population mean length of fourth-graders' feet, in cm.

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8.1.67

(a) (22.97, 23.22) (b) We are 95% confident that the population mean lies between 22.97 and 23.22. (c) 0.125 (d) We can estimate the population mean to within 0.125 with 95% confidence.