SOLUTION: If a student has an average exam score between 70 and​ 79, he will earn a grade of C in his algebra course. Suppose he has three exam scores of 77,64​,and 81 and that

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Question 1067950: If a student has an average exam score between 70 and​ 79, he will earn a grade of C in his algebra course. Suppose he has three exam scores of 77,64​,and 81
and that his teacher said the final exam score has twice the weight of the other three exams. What range of scores on the final exam will result in him earning a grade of​ C?

Answer by t0hierry(194) About Me  (Show Source):
You can put this solution on YOUR website!
(77 + 64 + 81 + 2*x)/(1 + 1 + 1 + 2) must be between 70 and 79
That is 77 + 64 + 81 + 2*x between 350 and 395
or 350 < 222 + 2x < 395
so 64 < x < 86.5