It would depend on the question.
Assuming that the questions have the same value, each one is worth 1.47 % of the maximum possible score.
You cannot know that. If you are told the total number of points for the test, you know (or count) the number of questions and you are told that each question is worth the same number of points then, and only then, each question is worth (total points/number of questions) points.
To calculate your grade, you need to know how much each question is worth. If each question is worth the same, you can divide the number of correct answers (80 - 3 = 77) by the total number of questions (80) and multiply by 100 to get a percentage. If each question is worth different points, you'll need to know the point value of each question to calculate your grade.
It depends on how many points each question is worth. If they are worth 1 point, 30, 2 points, 15, etc...
Depends on the test.
1.818... % of the total marks.
It would depend on the question.
There's no reason they all have to be worth the same credit. Butif they are, then the number is 2.5% for each correct answer.
That would be totally up to the examiner.
Assuming each question has the same number of marks, 1 question is worth 1.6666...% 100 divided by 60 = 1.66666666... However it is much more likely, especially if the test is in preperation for exams, that each question will be worth a different amount depending on the hardness of the question and how much detail/work needs to be put in to get the right answer, 1.66666...% is more an average of how much each question is worth, than how much each question is actually worth.
8 and 1/3%
Assuming that the questions have the same value, each one is worth 1.47 % of the maximum possible score.
If the test is worth 100 points, each question would be worth approximately 2.86 points.
It depends how many points each question is worth. If each question is worth five points on a twenty question test, you would get ninety-five percent.
If all the questions are worth the same and the whole test is 100 points, then each question is worth 12.5 points
Each question would be worth 2.5%