Question

Carver Memorial Hospital's surgeons have a new procedure that they think will decrease the variance in the time it takes to perform an appendectomy. A sample of 8 appendectomies using the old method had a variance of 36 minutes, while a sample of 10 appendectomies using the experimental method had a variance of 16 minutes. At a = .10 in a two-tailed test for equal variances, the critical values are Multiple Choice -1.645 and +1.645 0.299 and 3.07 () 0.368 and 2.51 0.272 and 3.29 O

Answer 1

solutions Giren: 52-36 52²=16 ni=8 n2=10 P = o.109 sulo 10 The null and alternative hypothesis is the Ho: 6,2 = 62 vs H1 : 6²7 62 Pf82.0 Critical value Lee FL- FC 1-8, hi-t, 12-1) so o = XR F(0.95, 7, 9) = F(0.95,7,9) face from table FL = 0.272 151 20 Fue Flagpil, 12-1) =F(0.05,7,9) From table = 3.293 Answer! 0.272 and 3.29