Statistics Undergrad Course
|2.||J. McWhorter of College of Health Science at the University of Nevada studied physical therapy students during their graduate-school year. The researchers were interested in the fact that, although graduate physical therapy students are taught the principles of fitness, some have difficulty finding time to implement those principles. A sample of 27 female graduate physical- therapy students had a mean of 22.46 percent body fat.
a. Assuming the percent body fat of females graduate physical-therapy students is normally distributed with a standard deviation of 5.10 percent body fat, determine a 95% confidence interval for the mean percent body fat of all female graduate physical- therapy students
b. Obtain the margin of error, E, for the confidence interval for the mean you found in part a.
c. Explain the meaning of E in this context in terms of the accuracy of the estimate
d. Determine the sample size required to have a margin of error of 1.55percent body fat with a 99% confidence level.