SOLUTION: Mark has an 80 average after 3 tests. He wants an average of 85. What must Mark make on his next test to have an average of 85?
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Question 1009595: Mark has an 80 average after 3 tests. He wants an average of 85. What must Mark make on his next test to have an average of 85?
Answer by addingup(3677) (Show Source): You can put this solution on YOUR website!
(3(80)+x)/4= 85
(240+x)/4= 85 multiply both sides times 4:
240+x= 340 now subtract 240 from both sides:
x= 100 Mark had better study hard!
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