exercise.txt

Today's exercise: more practice on instance and class contexts.

We're going to make a class that does two things:
   1) Instances are instantiated with two numbers, and the object can do math on them.

   2) The class keeps track of how many instances there are

I'm providing specs, you goal is: 
  1) Fill in the class that makes the specs pass

  2) Add a comment above each method explaining whether it's a class method or an instance method, and why you picked that option.
 
  3) Add a comment above each variable (in the first place you use it), explaining whether it's a class variable or an instance variable, and why you picked that option.