Using mean and outlier concepts, it is found that:
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Thus, the mean is:
[tex]M = \frac{80 + 92 + 91 + 75 + 89 + 84 + 0 + 85}{8} = 74.5[/tex]
Brandee's mean was of 74.5, which doesn't really represent her abilities, as in 7 of the 8 tests she got higher grades than this, but her mean is really affected by the outlier grade of 0%, for the test she missed.
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[tex]M = \frac{80 + 92 + 91 + 75 + 89 + 84 + 90 + 85}{8} = 85.75[/tex]
Brandee's new mean will be of 85.75, which increases her final grade by 11.25 points, and is a more accurate representation of her abilities, as there is not an outlier grade.
A similar problem is given at https://brainly.com/question/24097242