Chemistry Lecture and Lab Grading Question

I was told by my professor that he will take 20% from the Chem. Lab and add it to the lecture grade. For example:

Lecture Grade: 80 Plus the Lab, which I got about a 90.

(.20 x 90 = 18) 18 + 80 = 98 for the final grade.

This surprised me and I was wondering if this was the norm?

P.S. It was a pleasant surprise.


It depends on the school: I’ve attended colleges where the General (or sometimes called Inorganic) Chemistry grade was made-up of the lecture scores and lab scores, while at other colleges I’ve attended the lecture and lab grades were separate.


I don’t think you got it right because doing this way, assuming you got 100 in lecture and 100 in labs, you end up 120. So instead, I believe that your Professor meant that your final grade is composed of 80% for you lecture grade plus 20% for your lab grade. The 80/20 is a common way to weight lec and lab differently. In your case, that would mean that your final grade would be:

0.880 + 0.290 = 82

This way, assuming you score 100 in lec and 100 in labs, then you still end up with a total of 100.

I do hope that you are not too disappointed by my analysis, and perhaps I am getting it wrong.

That does make more sense. Who knows, he still might surprise the class. I will let you know when he posts the final grades.


you never know. You should just hope for the best at this point.

Good luck and sure, let me know.

My physical science class this past semester was graded together. THe lab being worth 15% of the total grade.