Question

Suppose a random sample of 23 items produces a sample standard deviation of 11. a. Use the sample results to develop a 90% confidence interval estimate for the population variance. b. Use the sample results to develop a 95% confidence interval estimate for the population variance. a. Iso²s (Round to two decimal places as needed.) b. sos (Round to two decimal places as needed.)

Answer 1

ܘ 90% internal - Solution : Given Sample size n=23 Standard deviation 3 - 11 confidence -> 421-confidence → 1-0.90 501) a Degree of predom of CM-D = 23-1=22 lower limit (entreal value) 22 77X0.05122 >> 33.9204 (from chisquare critical ceper limita value calculator) -«/zint c? 1-0.055,22 1698,2 ob ale inay & oila! 2 (crtical rales) 22 ) 12,33801 12.338 CI (A-D5² soc (n.Ds² gr alant 10/2inal (1) (103 G eos (24)(11)² 33-9244 12,3380 78.468 6 sot & 215,7562 78.47 % < 215.76 (Rounded to two deemas 95% con onfidence interval) nfidence 1000 E1-0.95 0:05 of no 1222 & appone = 2005 , 22 0.025, 22 36.7807

ne 22 (M) > u2 interral for varranc ! 1 72.37 Co seugile 1-1/2 1-0.05, 22 0.9751 22 10,9823 confidence (M-DS² chc (As² brutto dla.nl art 1-d/ani (22)(012) 72.3749 . n } (22) (11)² eon2 56-7807 VI 10-9823 11 2 c 242,3900 Rounded to two deamal places, 2