Basics of Engineering Economy 1st Edition by Leland Blank,Anthony Tarquin

Exercise 7

A construction company bought a 180,000 metric ton earth sifter at a cost of $5,000.The company expects to keep the equipment a maximum of 7 years.The operating cost is expected to follow the series described by 40,000 + 10,000k, where k is the number of years since it was purchased ( k = 1 through 7).The salvage value is estimated to be $0,000 for years 1 and 2 and $0,000 for years 3 through 7.At i = 10% per year, determine the economic service life of the sifter and the associated annual worth.