Question

Thao earned the following scores on her six management exams last semester.

79, 84, 44, 90, 79, 91
Thao has a chance to replace her score of 44 by taking a "make-up" exam. What must
she score on the make-up exam to get an overall average (mean) of 81?
She must get a score of
(Type a whole number.)
to get an overall average (mean) of 81.

Answer 1

Thao must score 63 on the make-up exam to achieve an overall average of 81 on her six management exams last semester.

Step-by-step explanation:

First, we calculate the total of Thao's current scores without the makeup exam:

• 79 + 84 + 44 + 90 + 79 + 91 = 467

Since the score of 44 is to be replaced, we subtract it from the total:

• 467 - 44 = 423

To find what Thao needs to score on the make-up exam to achieve an average of 81 for six exams, we use the formula:

• new average = (total of the scores + make-up exam score) / number of exams
• 81 = (423 + make-up exam score) / 6

Multiplying both sides by 6 to solve for the make-up exam score gives us:

• 486 = 423 + make-up exam score

Now subtract 423 from both sides:

• make-up exam score = 486 - 423
• make-up exam score = 63

Therefore, Thao must score 63 on the make-up exam to achieve an overall average of 81.