For a school fundraiser, Damon needs to sell 68 boxes of cookies. So far, he has sold 14 boxes of lemon cookies to his aunt, 6 boxes of chocolate cookies to his mother, and 10 boxes of oatmeal cookies to a neighbor. How many more boxes of cookies does Damon need to sell?
14 + 6 + 10 = 30
68 - 30 = ????