To determine the charge per minute based on the points provided (0,0), (15,50), and (90, x), we first need to recognize that these points represent a linear relationship.
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The point (0,0) indicates that there is no charge when no minutes are used (this is often the case with a flat fee plus a per-minute charge).
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The point (15,50) indicates that after 15 minutes, the total charge is $50.
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To find the per-minute charge, we can use the change in total cost divided by the change in minutes between the point (0,0) and (15,50).
Using the formula for the slope between two points: \[ \text{slope} = \frac{y_2 - y_1}{x_2 - x_1} \]
Plugging in the values from the points (0,0) and (15,50), we have: \[ \text{slope} = \frac{50 - 0}{15 - 0} = \frac{50}{15} = \frac{10}{3} \approx 3.33 \]
This means the company charges approximately $3.33 per minute.
Summary:
The cell phone company charges approximately $3.33 per minute.
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