To find the average number of enrollments per day, what you would want to do is add all of the numbers and then divide it by how many numbers there are.
Your Equation would look like this:
17+19+23+14+25+28 = ?
When you solve it. you would get:
126
126 would be the total amount of enrollments, but the question is asking you to find the average enrollments PER day. In this case, you would divide your total enrollments by how many numbers there are in the question. There are 6 numbers in the question, or six days, that being 17, 19, 23, 14, 25, and 28. So you would get your total amount of enrollments and divide it by 6
Your equation would look like this now:
126÷6=21
The average number of enrollments per day is 21.