13 - 4 = 9 correct
9/13 x 100 = 69% (rounded)
If by grade you mean percentage, you would have scored 67.5%. 40-13= 27 (27/40) * 100
77% or C+
If you got two wrong out of 15 questions, you would have answered 13 questions correctly. To calculate your grade, you would divide the number of correct answers by the total number of questions and multiply by 100. In this case, (13/15) x 100 = 86.67%. Therefore, your grade would be approximately 86.67%.
To calculate your grade, divide the number of correct answers by the total number of questions. If you missed 3 out of 13 questions, you got 10 correct. Therefore, your grade would be 10/13, which is approximately 76.9%. Depending on the grading scale, this would typically be a C or C+.
That would be a grade between 86% and 87%.
2 wrong out of 13 means 11 right out of 13 11/13 = 84.6% This typically translates to a solid B on many, if not most, grading scales. At Hogwarts it would probably be an A (Acceptable) - or possibly E (Exceeds Expectations) YMMV
10/13 right = 77% grade
Well, honey, if you got 4 wrong out of 17 questions, you'd have 13 correct. So, you take your correct answers, divide by the total questions, multiply by 100, and voila, you've got yourself a grade. Math doesn't lie, darling.
77% or C+
You use division. For example 13/47 is approximately 0.276 or 28%. 100-28 is 72 so the grade would be a 72.
12/13 correct is a 92% which is an A-
84.6 around that