81% = 75% Of The Total Grade & 80% = 25% 0f The Total Grade. How Do You Find The Average Grade?

Question

81% = 75% Of The Total Grade & 80% = 25% 0f The Total Grade. How Do You Find The Average Grade?

2 Answers

Answer Question

Answer 1

Ok so average out the 2. If the classroom grade is C but the reading grade is A or B, you should be able to pull the C up to a C+ or B if its vice versa, it'll pull the grade down some. If they both average out to be the same, chances are they will remain the same.
Hope this has helped =)

Answer 2

The weighted average grade is
grade = (81%)*(75%) + (80%)*(25%)
= .81*.75 + .80*.25 = .6075 + .2000 = .8075 = 80.75%
grade = 80.75%

Check:
The classroom grade is 1 point above the reading grade, but that point only counts for 75% of a point in the final grade. 1 point times 75% is .75 point, so the final grade is (80+.75)% = 80.75%.
_____
Here the weights add up to 100%. That is essential in such a problem. If the professor had said "classroom work counts 3 times as much as reading", then you would need to convert this to percentages that add to 100%: 3/(3+1) = 75% for classroom work, and 1/(3+1) = 25% for reading. (75% is 3 times 25%)