The following problems involve average rate of change.Cost of Gravel Wilson’s Sand and Gra...

The following problems involve average rate of change.

Cost of Gravel Wilson’s Sand and Gravel will deliver 12 yd3 of gravel for $240, 30 yd3 for $528, and 60 yd3 for $948. What is the average rate of change of the cost as the number of cubic yards varies from 12 to 30? What is the average rate of change as the number of cubic yards varies from 30 to 60?

Figure for Exercise 70