Three Category Grades

Want to know how to add and weight more than two grade categories?  It’s not really that much more complicated, it just makes the formula more convoluted.  I can add as many categories as I need, but I’d hate to think of the formula past a certain point.  Ultimately, the formula will look like this with three categories:

=SUM(cat1score x cat1weight, cat2score x cat2weight, cat3score x cat3weight)/SUM(cat1weight,cat2weight,cat3weight)

And so on it goes.  Here is an example from one of my gradebooks for a geography page.  I had grades for book work, presentations, and maps:

=SUM(C43*D43,C44*D44,C45*D45)/SUM(D43,D44,D45)

It gets long, but it doesn’t really get any more complicated.

I hope that helped.  To see a three-category grade in action, be sure to download the sample gradebook here.