Question

Is smoking during pregnancy associated with premature births? To investigate Type numbers in the this question, researchers selected a random sample of 130 pregnant women who were smokers. The average pregnancy length for this sample of smokers Part 2: 5 points was 260 days. From a large body of research, it is known that length of human pregnancy has a standard deviation of 16 days. The researchers assume that smoking does not affect the variability in pregnancy length. ab Part 1: 5 points 10 points Find the 999% confidence interval to estimate the length of pregnancy for women who smoke. (Note: The critical z-value to use, ze, is: 2.576) Your answer should be rounded to 3 decimal places.

Answer 1

Amawes Given that The auctoge Pnamcy longth tos this sample 0ET way i-e 260 days of Snokea Smokess e 130 who acse tamdom sumple 16 days Standand deviation hauc to fimd the 99y. comfidemcc imtcsua wc PIS-FOS the semgth of Peog mamay tos Ho csiamate coho Smo ke s womon At 99. comfidemce level the 2 88- :1-49. 2:1-99 l00 l:1-0.99 a:o.0 S00-00 2.570 20-005 O.O05

At 99. comnfidemce imlesval fos Slarmt Ksds 260 + 2.576x IG 3০ Ctnsto b 33C+32 2602.576 x 16 buoba 5 To 260 2.S7G 1-u032 260t 3.6148 ebmas p Lasas (263-614, 256-38 52) in .The 9. comfide nce imtesvalto estimate the Jemgth of Paegamc of wommem coho 263-614 256-385 Smoke :5 PP.