Junior high classes of 30 students each met in the cafeteria to take achievement tests. if exactly 5 students sat at each table and 24 tables were used, how many classes took the tests?

5 students sat at each table and 24 tables were used then 24*5 students were sitting =120 students.                                                                                              Every class is made of 30 students so to know how many classes took the test make 120/30 which gives you 4 classes