Question

To get a b in​ math, alexandria pappas must average 80 on five tests. scores on the first four tests were 84 ​, 78 ​, 82 ​, and 79 . what is the lowest score that she can get on the last test and still get a​ b?

Answer 1

The formula for averaging things is (a+b+c+d)/4 (because there are 4 items being added.)

So we want the average to be 80, so we set things equal to 80.

Let the score for the unknown test score be x.

80 = (84+78+82+79+x)/5

400 = 84+78+82+79+x

x = 77

The lowest possible score Alexandria can get is 77 points.