Sycamore Candy Company offers a CD single as a premium for every five candy bar wrappers presented by customers together with $2.50. The candy bars are sold by the company to distributors for 30 cents each. The purchase price of each CD to the company is $2.25; in addition it costs 50 cents to mail each CD. The results of the premium plan for the years 2010 and 2011 are as follows.