Question

Acid gases must be removed from other refinery gases in chemical production facilities in order to minimize corrosion of the plants. Two methods for removing acid gases produced the corrosion rates (in mm/yr) are listed below in experimental tests:

Method A: 0.3, 0.7, 0.5, 0.8, 0.9, 0.7, 0.8

Method B: 0.7, 0.8, 0.7, 0.6, 2.1, 0.6, 1.4, 2.3

Suppose the corrosion rates for both methods are normally distributed.

a. Determine the point estimate of the difference between the means of the two methods.

b. Estimate the ratio of variances for the two methods of removing acid gases in a 90% confidence interval.

c. Estimate the difference in mean corrosion rates for the two methods, using a confidence coefficient of 0.95. Hint: part b: Use F-interval part c: Use t-interval.

Answer 1