SOLUTION: In an algebra class a student has scores of 65, 72, and 84 on three exams. What score on the fourth exam is needed to make an average of at least 80%?

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Question 653909: In an algebra class a student has scores of 65, 72, and 84 on three exams. What score on the fourth exam is needed to make an average of at least 80%?
Answer by jim_thompson5910(35256) About Me  (Show Source):
You can put this solution on YOUR website!
(65+72+84+x)/4 >= 80

65+72+84+x >= 80*4

65+72+84+x >= 320

221+x >= 320

x >= 320-221

x >= 99

So you need at least a 99% on the fourth exam to make an average of 80% or better.