You know that the cost of the banners is increasing at a constant rate. Fill in the blanks in the table with the correct amounts. Then fill in the blank stating the rate of change.

Question

Number of banners	Total cost of banners	(in dollars)
10	42
20	72
30
40
50

The rate of change is $

 per banner.

Answer 1

So you know that from 10 to 20 banners, the total cost of the banners changes from 42 to 72. As we know it is increasing at a constant rate, we use the slope formula to find the rate of change. The slope formula is the change in the Y-values divided by the change in the X-values. So, (72 - 42) / (20 - 10) would give you the rate of change. The answer is 30/10, which means that for every 10 banners your total cost will increase by 30. Or if you simplify the answer, for every added banner, your total cost will increase by 3. With this information you can finish filling the table. I hope this answers your question and please let me know if you have any questions.