6. Since the rate of return on the extra investment is greater than the 12% MARR, the higher cost
vendor B is selected.
Comment
Once the spreadsheet is set up, there are a wide variety of analyses that can be performed. For
example, row 17 uses the NPV function to verify that the present worth is positive at MARR12%.
Charts such as PW versus i and PW versus i help graphically interpret the situation.