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.

Denote Time Used: Let's denote the time Famke used her phone as $ t $ minutes. According to the problem, she charged her phone for twice the amount of time, which is $ 2t $ minutes.Percentage Points Lost: When Famke uses her phone, it loses 5 percentage points each minute. So, if she used her phone for $ t $ minutes, the total percentage points lost would be $ 5t $.Percentage Points Gained: When Famke charges her phone, it gains 2 percentage points each minute. Since she charged it for $ 2t $ minutes, the total percentage points gained would be $ 4t $ (because $ 2 \times 2t = 4t $).Equation Setup: The problem states that after using and then charging her phone, Famke's phone lost 10 percentage points in total. We can set up the following equation to represent this situation: Loss from using the phone - Gain from charging the phone = Total loss $ 5t - 4t = -10 $Corrected Equation: Solving the equation $ 5t - 4t = -10 $ gives us $ t = -10 $. This result doesn't make sense because time cannot be negative. Therefore, we must have made a mistake in our equation. The correct equation should be: Gain from charging the phone - Loss from using the phone = Net loss $ 4t - 5t = -10 $

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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.

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

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Q. When Famke charges her phone, it gains

2

percentage points each minute. When Famke uses her phone, it loses

5

percentage points each minute.

\newline

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.

\newline

How long did Famke use her phone and how long did she charge it?

\newline

Choose

1

answer:

\newline

(A) There is not enough information to determine the exact time Famke used and charged her phone.

\newline

(B) The given information describes an impossible situation.

\newline

10

minutes, and charged her phone for

20

minutes.

\newline

(D) Famke used her phone for

20

minutes, and charged her phone for

10

minutes.

Denote Time Used: Let's denote the time Famke used her phone as $t$ minutes. According to the problem, she charged her phone for twice the amount of time, which is $2t$ minutes.
Percentage Points Lost: When Famke uses her phone, it loses $5$ percentage points each minute. So, if she used her phone for $t$ minutes, the total percentage points lost would be $5t$ .
Percentage Points Gained: When Famke charges her phone, it gains $2$ percentage points each minute. Since she charged it for $2t$ minutes, the total percentage points gained would be $4t$ (because $2 \times 2t = 4t$ ).
Equation Setup: The problem states that after using and then charging her phone, Famke's phone lost $10$ percentage points in total. We can set up the following equation to represent this situation: $\newline$ Loss from using the phone - Gain from charging the phone = Total loss $\newline$ $5t - 4t = -10$
Corrected Equation: Solving the equation $5t - 4t = -10$ gives us $t = -10$ . This result doesn't make sense because time cannot be negative. Therefore, we must have made a mistake in our equation. The correct equation should be: $\newline$ Gain from charging the phone - Loss from using the phone = Net loss $\newline$ $4t - 5t = -10$