For example, the maximum number of points for the course you may get is 700.
To get "A" grade you have earn from 630 to 700 points.
In other words, "A" grade is calculated from the total number of the points (700) you may get.
That is exactly the same as 100% (700 points), where 1% = 7 points.
Thus, to get "A" grade you have to earn 630 - 700 points, that is 90% - 100% range of the total amount of points.
For example, you have 5 assignments, 140 maximum points each.
You get:
1) 130 points out of 140 THAT IS 92.86%
2) 125 points out of 140 THAT IS 89.29%
3) 140 points out of 140 THAT IS 100%
4) 120 points out of 140 THAT IS 85.71%
5) 138 points out of 140 THAT IS 98.57%
TOTAL:
653 points out of 700 OR 93.29% out of 100%
It matches 90% - 100% scale (that's the same as 630 - 700 points) that gives you the "A" grade.
Basically you need the 'points' only to enter your grade (the number of points received and maximum possible).
The app will calculate the percentage automatically.