Question

A car that originally cost $20,000 depreciates by 15% each year. In about how many years will the car be worth half its value? Use the equation 10,000 = 20,000(8.5)^x to solve the problem. Round your answer to the nearest dollar.

Answer 1

It's

0.5=0.85^x take natural log of both sides...

ln0.5/(ln0.85)=x

x≈4.265 years the car's value will be half of its original value...

y=20000(0.85)^(4.265)

y=$10000.00