Bernice decides to look at a Horizon Unwired phone plan. The plan has a monthly charge and an activation fee. With this plan, she can get 10 months of service for $210 and 15 months of service for $292.50.

•Write a linear equation to represent the cost of the plan. Let C represent the total amount of money paid in dollars, and m represent the number of months of service. Show work.

•Use your equation to find the cost for 24 months of service.

Due to inflation, Horizon Unwired will increase either the activation fee by 50% OR increase the monthly charge by 10%.

•Which change would cost Bernice less money over two years? Support your reasoning with numbers and words.