SOLUTION: The athletic director of a school has found that 47 out of 65 football injuries occurred during practice. a) Write a 95% confidence interval for the proportion of football injuri

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Question 872399: The athletic director of a school has found that 47 out of 65 football injuries occurred during practice.
a) Write a 95% confidence interval for the proportion of football injuries that happen during practice.
b) A report by the NCAA states that 57.6% of football injuries occur during practice. Is the percentage of injuries during practice at the school significantly different from the national average? Use . Should the athletic director be concerned?
Answer by ewatrrr(24785) About Me  (Show Source):
You can put this solution on YOUR website!


Hi

a) 47/65 = p = .723 (72.3%)

  ME(95% confidence Interval) = 1.96sqrt(.723*.277/65) = .1 or 10%

  CI: 72.3% - 10%  < u < 72.3% + 10%

  CI: (62.3%, 82.3%)

b) Is 57.6% significantly different?  YES, definitely on the Low side