Engineering Economy 7th Edition by Leland Blank ,Anthony Tarquin

Exercise 62

A contractor purchased equipment costing $40,000 in 2010 when the M S equipment cost index was at 1461.3. He remembers purchasing the same equipment for $21,771 many years ago, but he does not remember the year that he did so. If the M S equipment cost index increased by 2.68% per year over that time period and the equipment increased in price exactly in proportion to the index,
a) in what year did he purchase the equipment and b) what was the value of the index in that year