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Cell phone A's battery has an initial charge of 15%. When plugged into the charger, it charges at a rate of 33% every 30 minutes. Cell phone B's battery has an initial charge of 0%. When plugged into the charger, it charges at the rate shown in the table below. Minutes Connected to the Charger 0 12 20 Percent Charged 0 27 45 Enter in response box 1 the cell phone battery, A or B, that charges at the greatest percentage rate. Enter in response box 2, the time, in minutes, that it will take cell phone B's battery to be 100% charged.

I kinda need it asap so that would be helpful :]



Cell phone A's battery has an initial charge of 15%. When plugged into the charger-example-1
User Praveen E
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1 Answer

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1. Cell phone A charges at a rate of 33% every 30 minutes, which means it charges at a rate of 1.1% per minute (33%/30min = 1.1%/min).

Cell phone B's charging rate is not given for all times, but we can use the two data points in the table to estimate its charging rate.

From 0 to 12 minutes, the battery charges by 27%, which means it charges at a rate of 2.25% per minute (27%/12min = 2.25%/min). From 12 to 20 minutes, the battery charges by 18%, which means it charges at a rate of 1.5% per minute (18%/8min = 1.5%/min).

Therefore, cell phone B charges at a greater percentage rate than cell phone A between 0-12 minutes of being connected to the charger. After 12 minutes, cell phone A charges at a greater percentage rate than cell phone B.

2. Let's assume that cell phone B charges at a constant rate between 0-20 minutes. To find the charging rate, we can use the two data points in the table:

From 0 to 12 minutes, the battery charges by 27%. From 12 to 20 minutes, the battery charges by an additional 18%. So, in total, the battery charges by 45% in 20 minutes.

Using this information,

we can set up a proportion to find the time it will take cell phone B's battery to be 100% charged:

20min / 45% = x / 100%

Cross-multiplying, we get:

45x = 2000

Dividing by 45, we get:

x ≈ 44.44

Therefore, it will take approximately 44.44 minutes (rounded to the nearest hundredth) for cell phone B's battery to be 100% charged if it charges at a constant rate.

User Yesthisisjoe
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