Algebra 1 Exponential Growth and Decay

Question

Your car cost $42,500 when you purchased it in 2015. The value of the car decreases by 15% annually. How much will your car be worth in 2022? Round your answer to the nearest dollar.

Answer 1

V(t) = 42500(0.85)^t

V(t) = 42500(0.85)⁷

Can you calculate and answer?

Answer 2

I'm using "interest" backwards:

fv=p(1+int/c)^(ct)

future value

principalint

compound

42500(1-.15)^7=$36520.49