Question

A normal population has a mean of 75 and a standard deviation of 5. You select a sample of 40. Use Appendix B1 for the z values Compute the probability that the sample mean is: (Round the zvalues to 2 decimal places and the final answers to 4 decimal places.) a. Less than 74 Probability 09 b. Between 74 and 76. Probability c. Between 76 and 77 Probability d. Greater than 77 Probability Not > 3 of 4 < Prey fire png fjpg arch

Answer 1

Answert Given that A noma populdion has a mean of 45 and stondeld deviction of 5. Sample mean follows a nome distribution with meon U-15 and Standud dochter 20.9906 7-wear z = standuld devitious 2. -45 0.7906 follows standeed nomel. @) PEH /2-75, 74-95) Plz -1.26) - 0.1028 PC-9442226) = P2296)-f(<74 J -95,94-95 -PL.796 0906 .256 = P/ 7-75, 76-75 1 0.9906 0.5906 - P(2<1.26)-P (32-1.26) 0-892-0-1038 0.2724.

p(762X297) - P 277) -PL276) 9-7576-15 0.976 0-3906 PX-5 279-95 0.2906 0.796 (222.53) - P(221.26 0-9943-0.8962 = 0.0981 d) Posa) DI 2-45 79-75 0.79060-7906 = P(2>2.53) = 1-P(252-53) 1-0.7943 0.0057