Applications of exponential function: Principal, rate, time.
A fax machine is purchased for $5,800. Its value each year is about 80% of the value of the preceding year. So after t years the value, in dollars, of the fax machine, V(t), is given by the exponential function
V(t) = 5800 (0.8)t.
a. Give a sketch of the graph of the function V(t). Your graph can be a "rough draft".
b. Determine the value of the fax machine in years 0, 1 and 4. to the nearest tenth.
c. Assume that the company decides to replace the machine when the machines values reduces to $500. In how many years will the machine be replaced.