Question

A phone company charges its customers as follows:
For the first 500 minutes used each month, the customer is charged a flat rate of $50. These 500 minutes are "included" in their monthly plan.
For any additional minutes used, the customer is charged an additional $.10 per minute.
Which type of function would best model this situation: a greatest integer function or a piecewise function that is not a greatest integer function? Explain.

Answer 1

Suggest that you actually graph the appropriate function. What would the graph look like for the first 500 minutes of calling?

Answer 2

Like a greater integer graph?

Answer 3

50 + .10x?

Answer 4

Can either of you now draw the 2nd part of this function? Hint: the 2nd part of the graph begins at (500,$50).