SOLUTION: In a class in which the final course grade depends entirely on the average of four equally weighted 100-point tests, Paul has scored 82, 88, and 87 on the first three. What range

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Question 1140893: In a class in which the final course grade depends entirely on the average of four equally weighted 100-point tests, Paul has scored 82, 88, and 87 on the first three. What range of scores on the fourth test will give Paul a C for the semester (an average between 70 and 79, inclusive)? Assume that all test scores have a non-negative value.
**Express your answer in interval notation**

Answer by greenestamps(13200) About Me  (Show Source):
You can put this solution on YOUR website!


4%2A70%3C=%2882%2B88%2B87%2Bx%29%3C=4%2A79
280%3C=257%2Bx%3C=316
23%3C=x%3C=59

ANSWER: [23,59]

Note the stated condition for getting a C is probably not correct. The statement says a C grade means an average in the interval [70,79]; probably the correct interval for getting a C grade is [70,80).

That will of course change the answer to the problem slightly.