Mary works selling cards over the telephone. She sells two types of cards: birthday cards and holiday cards. Mary makes $2.00 for each box of birthday cards she sells, and $2.50 for each box of holiday cards she sells. She can work no more than 10 hours per week. It takes
her an average of 15 minutes to sell one box of birthday cards, and an average of 20 minutes to sell one box of holiday cards.
If she can sell no more than 35 boxes of cards in total, how many boxes of each type should she sell to make the most money? (Hint:
remember that an hour contains 60 minutes!)
**needs 4 constraints!!**