Answer:
a. 80.25
b. 104
Explanation:
For (a), you add all the numbers together and divide by 4 because there are 4 test scores.
87 + 92 + 63 + 79 ÷ 5 = 80.25
For (b), we need to set up an equation. It is going to be a similar concept.
87 + 92 + 63 + 79 + x ÷ 5 = 85
x = 104
Hope this helps!