I took a graduate course (C.S) in a U.S university. We were not provided with any grading scale in the syllabus. I was assigned a letter grade but I have no idea how it was calculated. Below is an example of a grading scale from another course
If X is your overall course score, letter grades will be assigned
using the below scale. Scores will not be rounded.
100 ≥ X ≥ 93 A 93 > X ≥ 90 A- 90 > X ≥ 87 B+ 87 > X ≥ 83 B
83 > X ≥ 80 B- 80 > X ≥ 77 C+ 77 > X ≥ 73 C 73 > X ≥ 70 C-
70 > X ≥ 67 D+ 67 > X ≥ 63 D 63 > X ≥ 60 D- 60 > X ≥ 0 E
Can I ask the professor how my letter grade was calculated? if so, would something along the lines of "Could you please provide us with the grading scale used for the course or post it on Canvas?" be acceptable and non-offensive?