The price of Stock A at 9 a. M. was $15.54. Since then, the price has been increasing at the rate of $0.11 each hour. At noon the price of Stock B was $16.29. It begins to decrease at the rate of $0.12 each hour. If the two rates continue, in how many hours will the prices of the two stocks be the same?

Quick! a survey of 57 customers was taken at a bookstore regarding the types of books purchased. the survey found that 33 customers purchased mysteries, 25 purchased science fiction, 18 purchased romance novels, 12 purchased mysteries and science fiction, 9 purchased mysteries and romance novels, 6 purchased science fiction and romance novels, and 2 purchased all three types of books. a) how many of the customers surveyed purchased only mysteries? b) how many purchased mysteries and science fiction, but not romance novels? c) how many purchased mysteries or science fiction? d) how many purchased mysteries or science fiction, but not romance novels? e) how many purchased exactly two types of books?