Question

Ms. Colunga bought a new car, which cost him $30,000. Which equation represents how long it will take for the value of the car to be 15,000 if the car depreciates at a rate of 18% per year

Answer 1

3.5 years.

Explanation:

The formula for depreciation is as follows (I had to look it up too):

worth after time = initial worth * (rate)^t

In this case it depreciates which means that the rate is 1-0.18 = 0.82.

we know it will be worth 15,000,

So substituting would give us

`15,000= 30,000(0.82^(t))`

now we we need to solve for t, so we will end up with

1/2 = 0.82^t

log (1/2) = t log(0.82)

t =
`(log(1/2))/(log(0.82))`

Therefore, t is roughly 3.5 years.

Great question, hope this helps.