Car value

The car loses value 15% every year.

Determine a time (in years) when its price will halve.

Correct answer:

n =  4.265

Step-by-step explanation:

$$\begin{gathered} (1-{\displaystyle \frac{15}{100}}{)}^n=0.5 \\ n\ln (1-{\displaystyle \frac{15}{100}})=\ln 0.5 \\ n={\displaystyle \frac{\ln 0.5}{\ln (1-{\displaystyle \frac{15}{100}})}} \\ n=4.265 \end{gathered}$$

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