Kelly’s scores on her first two tests in Algebra were 52 and 89. What will she need to make on third test to have an average of at least 79?
Answer

96 or better

85 or better

79 or better

80 or better

Question

Kelly’s scores on her first two tests in Algebra were 52 and 89. What will she need to make on third test to have an average of at least 79?
Answer
		
96 or better
		
85 or better
		
79 or better
		
80 or better

queelius · Answer

The average is defined as the sum of the scores divided by the number of scores, e.g., if you get a 100 on test 1, 80 on test 2, and 90 on test 3, your average is:

(100 + 80 + 90) / 3 = 270 / 3 = 90

So, we want to solve the following problem:

$$\frac{ 52 + 89 + x }{ 3 } \ge 79$$

queelius · Answer

Solve for x.