Answer
a. i. 75% ii. 84%
b. Interval =[59.4, 132.3]
Work Step by Step
i. 91.8±k(16.2) = [59.4,124.2]
91.8-16.2k=59.4
k = 2
k=2, $1-\frac{1}{2^2} = 3/4*100 = 75%$
ii. 91.8±k(16.2) = [51.3,132.3]
91.8-16.2k=51.3
k=2.5
k=2.5, $1-\frac{1}{2.5^2} = (1-0.16) \times100 = 84%$
b. Interval = [91.8-2(16.2), 91.8+2.5(16.2)]
=[59.4, 132.3]