Question

A college math professor informs her students that rather than curving final grades, she will replace each students lowest test score with the next to lowest test score, and then re-average the test grades. If Leeza has test scores of $86,92,81,64$ and $83$, by how many points does her final test average change based on the professor's policy?

• A. $2$
• B. $3$
• C. $4$
• D. $5$

Answer 1

Answer: (C)

$4$

Step 1: Find the original test average:

$\frac{86+92+81+64+83}{5}=81.2$

Arrange the marks in order: $64,81,83,86,92$

Step 2: Find the average of the tests after replacing the lowest score $\left(64\right)$ with the next to lowest score $\left(81\right)$: $\frac{81+81+83+86+92}{5}=84.6$

Subtract the original average from the new average: $84.6-81.2=3.4$