Concept explainers
Salvage value. Wills Investments tracks the value of a particular photocopier over a period of years. The data in the table below show the value of the copier at time t, in years, after the date of purchase.
(Source International Data Corporation)
Time, t (in years) | Salvage Value |
0 | $34,000 |
1 | 22,791 |
2 | 15,277 |
3 | 10,241 |
4 | 6,865 |
5 | 4,600 |
6 | 3,084 |
a. Use regression to fit an exponential function
b. Estimate the salvage value of the copier after 7 yr; 10 yr.
c. After what amount of time will the salvage value be $1000?
d. After how long will the copier be worth half of its original value?
e. Find the rate of change of the salvage value, and interpret its meaning.
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