Lesson 3

Functions can also be written to help solve problems involving rates. Linear functions represent situations where a rate of change is constant.

 

Consider the following situation.

 

Rajesh’s sister, Akuti, is preparing for the move by finding a new cellphone plan. She intends to keep in contact with her friends through texting. She has two choices for an add-on texting plan: a pay-per-use plan and a texting bundle. Both plans only charge for outgoing text messages. Incoming texts are free. You can view Akuti’s Options to see the two plans.