Question

The amount of money, in dollars, Sarah has in her savings account is modeled as a function of time in months. This function is represented by the graph below. What is the average rate of change for the amount of money, in dollars per month, from month 0 to month 12?

Answer 1

The average rate of change is given by the change in the amount of money between 0 and 12 months, divided by the change in the months.

Notice that in month 12, she had $500. And in month 0, she had 200.

Thus, in dollars per month, this average rate of change is:

`(500-200)/(12-0)=(300)/(12)=25`

Therefore, the answer is:

$25 per month