Solve the problem.
-Michael gets test grades of 75, 79, 82, and 87. He gets a 88 on her final exam. Find the weighted mean if the tests each count for 15% and the final exam counts for 40% of the final grade. Round to one decimal place.
A) 83.7
B) 82.2
C) -77.8
D) 245.2

Question

Quizplus · Accepted Answer

To find the weighted mean, we first need to calculate the weighted sum of all the grades.

Weighted sum = (0.15 x 75) + (0.15 x 79) + (0.15 x 82) + (0.15 x 87) + (0.40 x 88) 
Weighted sum = 11.25 + 11.85 + 12.30 + 13.05 + 35.20 
Weighted sum = 83.65

Next, we divide the weighted sum by the total weight (which is 0.15 + 0.15 + 0.15 + 0.15 + 0.40 = 1).

Weighted mean = 83.65/1 = 83.7 (rounded to one decimal place)

Therefore, the best choice is A.

Solve the Problem. -Michael Gets Test Grades of 75, 79, 82, and 87