statistics help

Question

in​ Marissa's calculus​ course, attendance counts for 15​% of the​ grade, quizzes count for 15​% of the​ grade, exams count for 50​% of the​ grade, and the final exam counts for 20​% of the grade. Marissa had a 100​% average for​ attendance, 89​% for​ quizzes, 82​% for​ exams, and 85​% on the final. Determine​ Marissa's course average

Answer 1

Use the weighted average:

Grade = (0.15)(100%) + (0.15)(89%) + (0.50)(82%) + (0.20)(85%) = ____%