Sample

8.48 A assay of 20 pages was taken without replacement from the 1,591-page reflect directory Ameritech Pages Plus Yellow Pages. On each page, the mean scene of action of a function devoted to let out ads was measured (a display ad is a large block of multicolored illustrations, maps, and text). The selective information (in squ are millimeters) are shown below: 0 260 356 403 536 0 268 369 428 536 268 396 469 536 162 338 403 536 536 cxxx (a) Construct a 95 percent agency time breakup for the true mean. (b) Why ability normality be an proceeds here? (c) What experiment surface would be needed to receive an error of }10 unbowed millimeters with 99 percent self-reliance? (d) If this is non a intelligent requirement, suggest one that is. (Data are from a project by MBA student Daniel R. Dalach.) DisplayAds A: n=20, stand for x=346.5, old-hat deviation s=170.38 Since n<30, we must(prenominal) use t-table: d.f =19 For 95% confidence ?=0.05, a/2=0.02 5 From t-table at d.f=19=2.

093 office interval=346.5 2.903×(170.38/20)=346.5 79.74= (266.76, 426.24) Confidence interval is (266.76, 426.24) B: Normality whitethorn be an issue because the sample of 20 may not have been selected from the population in a random manner. C: Standard deviation=170.38 E=10=99%, Z=2.576 Sample size n=ZE2 D: 99% confidence may be besides high for a dissemination that may not be normal. Dropping the confidence may reduce the required sample size.If you want to get a full essay, order it on our website: OrderEssay.net

If you want to get a full information about our service, visit our page: write my essay