.
A professor grades students on three tests, four quizzes, and a final examination.
Each test counts as two quizzes and the final examination counts as two tests.
Sara has test scores of 75, 82, and 74.
Sara's quiz scores are 86, 72, 92, and 96.
Her final examination score is 75.
Use the weighted mean formula to find Sara's average for the course.
(Round your answer to one decimal place.)
~~~~~~~~~~~~~~~~~
From the condition, four quiz scores are 86, 72, 92 and 96 with the weight coefficient of 1 each;
three tests scores are 75, 82 and 74 with the weight coefficient of 2 each.
final examination score is 75 with the weight of 2*2 = 4.
So, the numerator is (86 + 72 + 92 + 96) + 2*(75 + 82 + 74) + 4*75 = 1108.
The number of different kind of quiz/tests/examinations, in terms of quizes, is
4 + 2*3 + 4*1 = 14.
The weighted average is
= = 79.1 rounded to one decimal place, as requested.
ANSWER. Using the weighted mean formula, Sara's average for the course is 79.1, rounded to one decimal place.
Solved.