the question is as follows.
Assume a student has got 4 assignments that will determine their final grade. Note, the grade ranges from 6-10. Assignment 'A' accounts for 15% of their final grade, 'B' accounts for 15%, C for 30% and D for 40%.
Am I wrong to assume that the students final grade would equate to: $\dfrac{15x+15y+30z+40w}{100}=F$ where $F$ is the final grade and {x,y,z,w} is their respective grades in {A,B,C,D}.
For example, if the student for the following results: A: 6 B: 10 C: 7 D: 10
Their final grade would be:
$\dfrac{15(6)+15(10)+30(7)+40(10)}{100}=\dfrac{17}{2}=8.5$