Word Problem on a Quiz I Had

Question

A Honda Civic is purchased for $25,000 and its value decreases each year by 20%. What is the value of it in five years? When will it be half of its original price?

Answer 1

IF you want an exact answer to when it will be worth 1/2 its original price or 12,500

We would say 12,500=25000 x (.8)^x

(0.8)^x = 0.5 Taking the log of both sides gives us

x(log 0.8) =log (0.5)

x= log 0.5/log0.8

x=3.1 years

Answer 2

V₅ = 25000(0.80)⁵

25000

20000

16000

12800

10240

Slightly after four years.