A cell phone company charges a flat fee plus an additional charge per minute. If the graph contains the points (0, 15) and (50, 90), what is the fee the company charges per minute? Give your answer in exact change.

Answer 1

To analyze the information given, we need to understand the points (0, 15) and (50, 90) in terms of the cost structure of the cell phone company.

Let \( m \) be the additional charge per minute, and let \( f \) be the flat fee. According to the information provided:

1. When no minutes are used (at \( x = 0 \)), the cost is \( 15 \): \[ f = 15 \]

2. When 50 minutes are used (at \( x = 50 \)), the total cost is \( 90 \): \[ f + 50m = 90 \]

Since we know that \( f = 15 \), we can substitute this value into the second equation: \[ 15 + 50m = 90 \]

Now we can solve for \( m \): \[ 50m = 90 - 15 \] \[ 50m = 75 \] \[ m = \frac{75}{50} = \frac{3}{2} = 1.5 \]

Therefore, the fee the company charges per minute is \( \boxed{1.5} \).