I need to know how to simplify expressions. Specifically decimal expressions for example 18.18 + 22.74

What is the difference between regular convex and concave polygons

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?

Fa bus driver leaves her first stop by 7: 00 a.m., her route will take less than 37 minutes. if she leaves after 7: 00 a.m., she estimates that the same route will take no less than 42 minutes. which inequality represents the time it takes to drive the route, r?