Michael went to the grocery store and bought bottles of soda and bottles of juice. Each bottle of soda has 40 grams of sugar and each bottle of juice has 20 grams of
sugar. Michael purchased a total of 11 bottles of juice and soda which collectively
contain 300 grams of sugar. Write a system of equations that could be used to
determine the number of bottles of soda purchased and the number of bottles of juice
purchased. Define the variables that you use to write the system.

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?