Chapter 10.4B, Problem 7A

a. Mr. Alberto wanted to count the score on a term paper as $60\%$ of a final grade, homework as $25\%$ of the grade, and the final exam as the remainder of the grade. A student in the class made 85 on the term paper, had a $78$ average on homework, and scored $90$ on the final exam. What number could Mr. Alberto use to determine the student’s grade if he used his grading scheme?

b. Write an algebraic expression to generalize the scoring procedure for Mr. Alberto’s class to allow him to use any percentages he likes for the scoring scheme. Clearly describe what the variables represent.