SOLUTION: Mr. Nelson lost one of his student's test papers. He knows that the other 4 students scored as follows: 93, 86, 86, 84. He also knows that the average score is 88.2. What is the sc

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Question 752836: Mr. Nelson lost one of his student's test papers. He knows that the other 4 students scored as follows: 93, 86, 86, 84. He also knows that the average score is 88.2. What is the score on the missing paper?
Answer by Okeke_Christian(26) About Me  (Show Source):
You can put this solution on YOUR website!
Let the score on the missing paper be x.


If he lost score of 1 student and has score of other 4, it means he has a total of 5 students!
Mean (Average) = Total Score / Number of Students.
We have,
Mean (Average) = 88.2 = 882/10;
Total Score = (93+86+86+84)+ x = 349+x
Number of Students = 5;
%28882%2F10%29+=+%28349%2Bx%29%2F5
Cross Multiply
%28882%2A5%29=10%2A%28349%2Bx%29
4410=3490%2B10x
4410-3490=10x
920=10x
Divide through by 10:
%28920%2F10%29=%2810x%2F10%29
92=x
Therefore, missing score is 92