SOLUTION: A student must have an average grade of 90 or grater on five tests in a course to get a grade of A. The student has grades of 84, 93, 92, and 89 on the first four tests. What possi

Algebra ->  Algebra  -> Inequalities -> SOLUTION: A student must have an average grade of 90 or grater on five tests in a course to get a grade of A. The student has grades of 84, 93, 92, and 89 on the first four tests. What possi      Log On

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Question 131207: A student must have an average grade of 90 or grater on five tests in a course to get a grade of A. The student has grades of 84, 93, 92, and 89 on the first four tests. What possible scores on the fifth test would resalt in a grade of A for the student?
Thanks a lot.
Answer by Earlsdon(6103) About Me  (Show Source):
You can put this solution on YOUR website!
To get an average grade of 90 or better (>or= 90), let the grade on the fifth test be x, then find the average of the five test scores.
%2884%2B93%2B92%2B89%2Bx%29%2F5+%3E=+90 Add the four scores and multiply both sides by 5.
358%2Bx+%3C=+450 Subtract 358 from both sides.
x+%3C=+92
The student has to score at least 92 on the fifth test to get an average grade of 90 on the five tests.