The gradebook in Moodle is very powerful with several options for aggregating and presenting grades to students. 

Once your course is created in Moodle and your syllabus is finalized, you are ready to set up your Moodle Gradebook.  Refer to your syllabus when setting up the Grade Items and Categories in your Gradebook.

Weighted Mean of Grades Aggregation Method: 

If you wish to weight grades differently in your course, then you want to set up your gradebook using the weighted mean of grades in categories method.  Here's how:

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Natural (Sum) Aggregation Method:

If you wish to grade based on a percentage of the sum of points, then you want to set up your gradebook using the Natural aggregation method.  Here's how:

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