In​ Marissa's calculus​ course, attendance counts for 10​% of the​ grade, quizzes count for 20​% of the​ grade, exams count for 55​% of the​ grade, and the final exam counts for 15% of the grade. Marissa had a 100% average for​ attendance, 89​% for​ quizzes, 82% for​ exams, and 81% on the final. Determine​ Marissa's course average.

.10*100 + .20*89 + .55*82 + .15*81 ≈ 85

I would do it this way:

1.0(.1) + .89(.2) + (.82)(.55) + .81(.15)
= .8505

or 85%

To determine Marissa's course average, we need to calculate the weighted average of each component.

Step 1: Calculate the weighted score for attendance.
Attendance grade = 100%
Weightage of attendance = 10%
Weighted attendance score = (Attendance grade * Weightage of attendance) / 100
Weighted attendance score = (100 * 10) / 100
Weighted attendance score = 10%

Step 2: Calculate the weighted score for quizzes.
Quiz grade = 89%
Weightage of quizzes = 20%
Weighted quiz score = (Quiz grade * Weightage of quizzes) / 100
Weighted quiz score = (89 * 20) / 100
Weighted quiz score = 17.8%

Step 3: Calculate the weighted score for exams.
Exam grade = 82%
Weightage of exams = 55%
Weighted exam score = (Exam grade * Weightage of exams) / 100
Weighted exam score = (82 * 55) / 100
Weighted exam score = 45.1%

Step 4: Calculate the weighted score for the final exam.
Final exam grade = 81%
Weightage of the final exam = 15%
Weighted final exam score = (Final exam grade * Weightage of the final exam) / 100
Weighted final exam score = (81 * 15) / 100
Weighted final exam score = 12.15%

Step 5: Calculate the overall course average.
Course average = Weighted attendance score + Weighted quiz score + Weighted exam score + Weighted final exam score
Course average = 10% + 17.8% + 45.1% + 12.15%
Course average = 85.05%

Therefore, Marissa's course average is 85.05%.

To determine Marissa's course average, we need to calculate the weighted average using the percentages given for each category of the grade. Here's how to do it:

1. Start by calculating the weighted average for each category:
- Attendance average: 100% × 10% = 10%
- Quiz average: 89% × 20% = 17.8%
- Exam average: 82% × 55% = 45.1%
- Final exam grade: 81% × 15% = 12.15%

2. Add up the weighted averages for each category:
10% + 17.8% + 45.1% + 12.15% = 85.05%

3. Marissa's course average is 85.05%.

Therefore, Marissa's course average is 85.05%.