In one class, homework is worth 4040% of the final grade, each of 3 projects is worth 1010%, and a final exam is worth 3030%.
(a) if a student has an 8585 homework average and a 9696 on the first project, what is the student's grade at this point?
(b) if a student gets a 7878 on the second project and a 7979 on the third project, what is the lowest grade the student can get on the final exam to get an 8080 overall in the course?