An online store sells CDs for $12 each and movies for $15 each. Yolanda bought c CDs and m movies for $150.
Last football season, Demarcus had scored a total of 150 points. In the next game, c, he scored 12 points and in the second game, m, he scored 12 points.
Best Bakery sells cakes for $12 each and muffins for $15 per dozen. One day, the bakery sold c cakes and m dozen muffins for total revenue of $150.