Every four years the value of a Chevy Cabalier is reduced by half.

Question

Purchase price $15,375
After t years of ownership:
Age of car: Value:
0 15,375
4 7,687.50
8 3,843.75

If P is price after t years, Which would be a good model for the values above?

a) P(t) = 15,375 (2)^t
b) P(t) = 15,375 (1/2)^t
c) P(t) = 15,375 (1/2)^t/4
d) P(t) = 15,375 (2)^t/4

Answer 1

The general formula for a "half-life" problem is

Value = original(1/2) ^(t/k) , where k is the half-life period.

so what do you think?

Answer 2

I think C