Finding a final amount in a word problem on exponential growth or decay

A car is purchased for $30,000. After each year, the resale value decreases by 20%. What will the resale value be after 4 years?

Use the calculator provided and round your answer to the nearest dollar.



Answer :

Let's solve this step-by-step:

1. Initial Value: The initial value of the car is [tex]$30,000. 2. Decay Rate: The car decreases in value by 20% each year. 3. Time Period: We need to find the value of the car after 4 years. The formula to calculate the depreciated value of an asset, given an initial value, a decay rate, and a time period, is: \[ V_f = V_i \times (1 - r)^t \] where: - \( V_f \) is the final value after the time period. - \( V_i \) is the initial value. - \( r \) is the decay rate. - \( t \) is the time period. Given: - \( V_i = 30,000 \) - \( r = 0.20 \) - \( t = 4 \) Let's substitute these values into the formula and calculate step-by-step. 1. First Year: \[ V_1 = 30,000 \times (1 - 0.20) = 30,000 \times 0.80 = 24,000 \] 2. Second Year: \[ V_2 = 24,000 \times (1 - 0.20) = 24,000 \times 0.80 = 19,200 \] 3. Third Year: \[ V_3 = 19,200 \times (1 - 0.20) = 19,200 \times 0.80 = 15,360 \] 4. Fourth Year: \[ V_4 = 15,360 \times (1 - 0.20) = 15,360 \times 0.80 = 12,288 \] So, the resale value of the car after 4 years is $[/tex]12,288 when rounded to the nearest dollar.