Question 575101
The calculations can be done most easily by using a spreadsheet, or some other special software. Just using a calculator would be very tedious. In any case, a lot of checking is necessary, because students who find grading mistakes can turn very nasty.
60% of anything is that anything times 0.60.
If a student answered 100% of the questions correctly in the first part of the exam, you would multiply that 100% score times 0.60 to get the 60 points earned in that part. If the same student only answered correctly half of the questions on the second part, the 50% score for the second part would get multiplied by 0.40 (because the second part is wort 40% of the total) and that would be added. SO the students grade would be (100%)(0.60)+(50%)(0.4)=60%+25%=85%
In general grades are first calculated as fractions. If all questions in a section of the exam are assigned the same value, the first calculation for the grade would be
correct answers divided by total questions.
If some questions are worth 1 point, and others two points, or something like that the first calculation would be
points earned divided by points possible.
Fractions are turned to percentages by just doing the division, so 52 correct answers out of 57 questions all with the same point value would be
{{{52/27=0.9123}}} which is rounded as 91%.
If you have sections of the exam that will have different weighings, you do not need to calculate percentages for each section. You can keep working with the fractions (or decimals) and just translate the final result to percentage.
For example, 52 out of 57 possible points in the first section worth 60% plus 3 out of 4 essay questions answered correctly in the second part worth 40%, would calculate as
{{{(52/57)*0.60+(3/4)*0.40=0.9123*0.60+0.75*0.40=0.5474+0.3000=0.8474}}} which would yield a grade of 85%.