5.61 a. Ho : H After - H Before 0 which implies Ho : H After H Before t = 0.88 _ p_ value = 0.2009 > 0.05 There is not evidence that the mean change in mpg is greater than 0, i.e., the mean mpg does not appear to be increased after installing the device. b. (_2.26, 6.48) - Reject Ho : M #. if Mo is less than the lower limit of the C.I., we fail to reject H 5.62 a. Let AC = MAfter - HBefore. The probabilities of Type II error with d = (42- are 7.54 given here: HC 1.0 2.0 3.0 4.0 5.0 6.0 7.0 8.0 9.0 d 0.13 .27 .40 0.53 0.66 .80 .93 1.06 1.19 B (Ha ) 0.89 0.81 0.68 0.54 0.39 0.25 0.14 0.07 0.03 b. The sample size should be increased. 5.63 a. Los = 5, U 05 = 16 b. L.05 = 6, U.05 = 15 The intervals are somewhat narrower. 5.65 Reject H. if B > 20 5.67 Reject H. if B 33 5.69 a. The normal probability plot is given here