Question

Question 1 4 pts For the following problem, use the given information to find the number of degrees of freedom, the critical values x' and xr, and the confidence interval estimate of o. You may assume that a simple random sample has been selected from a population with a normal distribution. Keep your numerical answers rounded to 3 decimal places. For a sample of pulse rates in a population of patients in a locality: 90% confidence; n = 66, s = 8 beats, i = 83 beats. A. B. C. DF- 22 XR = 90% CI estimate of o = Lower Limit: Upper Limit: HTML Editor B il il

Answer 1

solution:-

given that n = 66 , s = 8 , x̅ = 83

A. DF = 65

B. X^2 L = 84.821

C. X^2 R = 47.450

=> 90% CI estimate of σ = (7.003,9.363)

lower limit = 7.003

upper limit = 9.363

explanation for confidence interval

=> confidence interval formula for σ

=> sqrt((n-1)s^2/X^2 L) < σ < sqrt((n-1)s^2/X^2 R)

=> sqrt(65*8^2/84.821) < σ < sqrt(65*8^2/47.450)

=> (7.003 < σ < 9.363)