The battery life of a certain cell phone starts at 8 hours. The battery life decreases at an annual rate of 30%.a. Write a function that represents the battery life y after x years.

Solution

Solution

Amount before reduction : 11.42857 \dots

Solution steps

Translate the problem into an equation:

8 = x - 0.3 x

8 = x - 0.3 x : x = \frac{80}{7}

\frac{80}{7} = 11.42857 \dots

Amount before reduction : 11.42857 \dots

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