To calculate the course score roll-up, you need to look at the unit scores and the number of units in the course. Let's take a simple example of a course with 10 units. Once you have each unit score, add them up and then divide by the number of units.
So, the overall grade for the course is the sum of its units divided by the number of units:
75% + 85% + 80%+ 72% + 80% + 87% + 90% + 92% + 85% + 90% = 836% / 10 = 83.6
The course grade is then 83.6%.