Problema Solution
Roscoe Middle School tries to maintain an average class size of 20 students or fewer. On Monday, it averaged exactly 19 students per class. On Tuesday, 5 new students enrolled, causing an additional class to be added. What is the maximum and minimum possible values for the average class size?
Answer provided by our tutors
there is not enough information to answer this problem because there is no correlation between average class size and number of classes; if this is a 5000-class school, then the answer is quite different from a 5-class should
if there are 5 classes, then average went from 19 students per class to 20 students per class
the best answer is to assume that they were able to keep their class size below 20 students or fewer and the range is therefore (19, 20]
note that the range is open-ended for 19 since the additional of any new students means an exact average of 19 is no longer possible [unless there were students departing!]
the range is close-ended for 20 because we assume the school never has a case in which the average rises above 20
now, of course, maybe they had to create a new class, as in an instance of a school with only 1 classroom, then the average per class becomes 12, 24 students divided among the two classrooms