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Estimating Useful Life and Percent Used Up The property and equipment footnote from the Deere & Company Equipment and Operations segment follows. Property and Depreciation A summary of property and equipment at October 31 follows. Useful Lives* Property and Equipment ($ millions) (Years) 2015 2014 Land $114 $120 Buildings and building equipment 3,460 3,037 Machinery and equipment 5,499 5,089 Dies, patterns, tools, etc 1,567 1,552 All other Construction in progress 530 Total at cost 11,860 11,217 Less accumulated depreciation 5,846 5,694 Total $6,014 $5,523 *Weighted averages 23 11 8 5 875 889 345 Total property and equipment additions in 2015, 2014 and 2013 were $666 million, $1,016 million and $1,158 million, and depreciation was $692 million, $696 million and $637 million, respectively. a. Compute the average useful life of Deere's depreciable assets at year-end 2015. Round answer to one decimal place. 16.48 * years b. Estimate the percent used up of Deere's depreciable assets at year-end 2015. Round answer to one decimal place (ex: 0.2345 = 23.5%) 5.75 * % Check