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2 years ago

5

Elaine gets quiz grades of 71, 75, and 64. She gets a 60 on her final exam. Find the weighted mean if the quizzes each count for

20% and the final exam counts for 40% of the final grade. Round to one decimal place.

2 answers:

postnew [5]2 years ago

8 0

Answer

Find out the weighted mean .

To prove

As given

Elaine gets quiz grades of 71, 75, and 64.

She gets a 60 on her final exam

if the quizzes each count for 20% and the final exam counts for 40% of the final grade.

20 % is written in the decimal form

$= \frac{20}{100}$

= 0.20

40 % is written in the decimal form

$= \frac{40}{100}$

= 0.40

20% of 71 = 0.20 × 71

= 14.2

20% of 75 = 0.20 × 75

= 15

20% of 64 = 0.20 × 64

= 12.8

40% of 60 = 0.40 × 60

= 24

Thus

Weighted mean = 14.2 + 15 + 12.8 + 24

= 66

Elza [17]2 years ago

5 0

<span>1. Quizzes (10% each):

60 x 10/100 = 6
69 x 10/100 = 6.9
68 x 10/100 = 6.8

2. Exam (70%)

65 x 70/100 = 45.5

Add them all up now:

6 + 6.9 + 6.8 + 45.5 = 65.2

Therefore, answer is </span><span>65.2</span>

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