Question

A new car is purchased for 18500 dollars. The value of the car depreciates at 10.75%

per year. To the nearest year, how long will it be until the value of the car is 5000 dollars?

Answer 1

the answer is 12

Explanation:

It is not 11.5 because you have to round up and I just put 11.5 in and it said that it was wrong and 12 was right.

Answer 2

Answer: 11.5 years

Explanation:

Hi, to answer this question we have to apply an exponential decay function:

A = P (1 -r)^ t

Where:

p = original value

r = depreciation rate (decimal form) = 10.75 /100= 0.1075

t= years

A = value after t years

Replacing with the values given:

5000 = 18500 (1- 0.1075)^t

Solving for t:

5000/18500 = (1- 0.1075)^t

0.27027027 = 0.8925 ^t

ln 0.27027027= ln 0.8925 ^t

ln 0.27027027=t ( ln 0.8925)

ln 0.27027027/ ln 0.8925 =t

11.5 years =t

Feel free to ask for more if needed or if you did not understand something.