The Moodle gradebook offers quite a bit of flexibility in setting up your grading method. There are numerous ways you can aggregate grades such as Simple weighted mean of grades, Weighted mean of grades, and natural. The most common aggregation method is weighted mean of grades. Using this method you can determine how much weight to give each item and/or category. The default is Simple weighted mean of grades which determines the weight of each item based on its maximum allowable points. One of the most common grading methods is Weighted means of grades. Use this method if you would like to setup your gradebook in a way that gives a weight to certain items or categories such as Homework- 15%, Exam- 1 25%, Final Exam- 25%, Research Project- 35%.
For more information on these methods see the Moodle documentation on aggregation: https://docs.moodle.org/28/en/Grade_aggregation
To set weights start by going to the Categories and Items view from the dropdown menu on the gradebook screen.
Next choose edit settings from the Edit link to the right of the course title at the top of the list of Categories and Items.
On the edit settings page you can then choose the aggregation method you wish to use.
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