Question

Timelimit: 2 hours, 30 minutes, 1:41:58 remaini Show Intro/Instre "Durable press" cotton fabrics are treated to improve their recovery from wrinkles after washing "Wrinkle recovery angle" measures how well a fabric recovers from wrinkles Higher is better. Here are data on the wrinkle recovery angle (in degrees) for two types of treated fabrics: Permafresh 10 14 15 12 11 16 13 Hylite 12 14 19 16 20 A manufacturer wants to know how large is the difference in mean wrinkle recovery angle. Give a 95% confidence interval for the difference in mean wrinkle recovery angle: the decimal way we decimal

Answer 1

Date solution - (14)951. confidence interval for difference wrinkle recovery angle ie. (lx-lly) is, mean {(x-7) - 2 & 6 (767)+22 6x 67 calculation; (1-x) = 0.95 0.05 0.025 2 To.rs 1.96 mean for permafresh ic. x = 91 7 ý 13 variance for permafresth ElX;-)? 6

Date 28 7 mean for Hylite. ET 86 S 17.2 variance for Hylite 22.8 = 4.56. (7-8) - ZaV6 + 6 4 + ( 13 - 17.2) - 1969 9.56 S -6.5870

2 (79) + Z. V o + = (13-17.2) + 1.961 1 + f 1991 9.56 S A - 1.813. lower limit - upper limit -6.587. 7.873. وز confidence interval for wrinkle recorgery (-6.587, 7:813). mean difference angle is.