When Famke charges her phone, it gains 2 percentage points each minute. When Famke uses her phone, it loses 5 percentage points each minute. Once, Famke used her phone for some time, and then charged it for twice the amount of time she used it. In the end, her phone lost 10 percentage points. How long did Famke use her phone and how long did she charge it? Choose 1 answer: (A) There is not enough information to determine the exact time Famke used and charged her phone. B The given information describes an impossible situation. (C) Famke used her phone for 10 minutes, and charged her phone for 20 minutes. (D) Famke used her phone for 20 minutes, and charged her phone for 10 minutes.

Let's break it down! Famke used her phone for some time, let's call that "x" minutes. During this time, her phone lost 5 percentage points per minute, so it lost 5x points in total. Then, she charged her phone for twice the time she used it, which is 2x minutes. While charging, it gained 2 percentage points per minute, resulting in a total gain of 2(2x) = 4x points. The problem states that in the end, her phone lost a total of 10 percentage points. The change in battery percentage gives us: - Total Loss = 5x - Total Gain = 4x - Final Change = Total Gain - Total Loss = 4x - 5x = -x So, we have -x = -10, which results in x = 10 minutes for usage. Hence, she charged for 20 minutes. So, the answer is (C) Famke used her phone for 10 minutes, and charged her phone for 20 minutes. Now, isn't it fun to see how math can untangle real-life scenarios in such straightforward ways? Just remember that setting up equations allows you to visualize time and energy transfers and can often lead you to a solution, just like Famke's phone was charging right back up!