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3 years ago

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Question 18(Multiple Choice Worth 1 points) (01.01) Period 1 has 15 students in it and a test average of 86%. Period 2 has 21 st

udents in it and an average of 88%. Period 3 has 12 students in it and an average of 95%. Use weighted means to find the overall average of the classes.

1 answer:

andrew11 [14]3 years ago

8 0

Answer:

89.125%

Step-by-step explanation:

The weighted mean is simply the multiplication of the number of student in each period times the respective average of said period, divided by the total number of students:

Average = $\frac{15* 86 + 21*88 + 12*95}{15 + 21 + 12}$ = 89.125%

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