Question

What fractional part of the battery is still operating after 50 hours of use?

Answer 1

Fractional part of battery: B

t: hours

$B=5^{-0.02t}$

After 50 hours of use:

Substitute the t in the equation by 50 and evaluate:

$\begin{gathered} B=5^{-0.02(50)} \\ \\ B=5^{-1} \\ \\ B=\frac{1}{5^1} \\ \\ B=\frac{1}{5} \end{gathered}$Then, 1/5 of the battery is still operating after 50 hours of use