I'm hoping this is a very basic question for someone.

I am comparing some statistics from a private language school over two years:

In one year there were 120 classes with an average of 7.3 students per class
In the second year there were 140 classes with an average of 9.5 students per class

Obviously, I know can already see that the average of 9.5 students is higher than 7.3, but what influence does the number of classes have on this?

Is there a sum to be done between the number of classes and the average that will give me more detailed information regarding how more successful one year was than the other (the higher the average the more economical the class as it is a private school).

Thanks in advance.