SOLUTION: Suppose that you have scores of 86,93,80,and 88 on four exams in your algebra class. What score will you need on the fifth exam to have an average of 90?

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Question 49620: Suppose that you have scores of 86,93,80,and 88 on four exams in your algebra class. What score will you need on the fifth exam to have an average of 90?
Answer by Earlsdon(6294) About Me  (Show Source):
You can put this solution on YOUR website!
Recall that "average" means the sum of the numbers divided by how many numbers you added up.
You need the average of 5 tests to be 90. The five scores will be:
86, 93, 80, 88, and x. Find the average:
%2886%2B93%2B80%2B88%2Bx%29%2F5+=+90 Add the numbers and multiply both sides by 5.
347%2Bx+=+450 Subtract 347 from both sides.
x+=+103 is the required score on the fifth test.