Solve the Problem $r = 1 - \left( \frac { V } { C } \right) ^ { 1 / n }$

Multiple Choice

Solve the problem.
-The yearly depreciation rate for a certain vehicle is modeled by $r = 1 - \left( \frac { V } { C } \right) ^ { 1 / n }$ , where V is the value of the car after n years, and C is the original cost.
a. Determine the depreciation rate for a car that originally cost $18,000 and is worth $11,000 after
3 yr. Round to the nearest tenth of a percent.
b. Determine the original cost of a truck that has a yearly depreciation rate of 14% and is worth
$12,000 after 5 yr. Round to the nearest $100.

A) a. 15.1% per year; b. $25,500
B) a. 77.2% per year; b. $25,500
C) a. 77.2% per year; b. $14,000
D) a. 15.1% per year; b. $14,000