Question

Listed below are speeds (min) measured from traffic on a busy highway. This simple random sample was obtained at 3:30 P.M. on a weekday. Use the sample data to construct a 90% confidence interval estimate of the population standard deviation 65 64 64 56 64 52 59 58 59 70 62 68 Click the icon to view the table of Chi-Square critical values. The confidence interval estimate is min<o<milh. (Round to one decimal place as needed.)

Answer 1

Solukon Criven that n=12 64 65 4225 64 4096 64 4096 56 3136 4096 52 2704 59 948) 58 3364 59 3481 4goo 62 3844 68 4624 741 46047 The sample meen con ompeteel, 741 a 61.75 x = 12 Also, the sample Variances? is. 2 3 = n (740² 46047- to 12-1 764 26.386 continue

Chiron that 0²= 26.386, X = 61.75, n = 12 90% confidence interval for c- go% 1-0.90 = 0.1 0.05 0.95 d. f = = 12-1 = 11 x 0.05,11 9.67 ta, dif Vyd.fr 0.46,44 4.574 At 90% confidence interval for 6 (n-g² L 6 C [(n-1) s² xigidof Xo, dif (12-1) 26.386 (12-1) 26.386 264 19.67 4.574 L64 7.965 3.84) Ansoor The confidence interval estimate is 3.8 mi/h 268.0