SOLUTION: In a class in which the final course grade depends entirely on the average of four equally weighted 100-point tests, Lisa has scored
76,
91, and
83 on the first three. What
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-> SOLUTION: In a class in which the final course grade depends entirely on the average of four equally weighted 100-point tests, Lisa has scored
76,
91, and
83 on the first three. What
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Question 1017435: In a class in which the final course grade depends entirely on the average of four equally weighted 100-point tests, Lisa has scored
76,
91, and
83 on the first three. What range of scores on the fourth test will give Lisa a B for the semester (an average between
80 and
89, inclusive)? Assume that all test scores have a non-negative value.
Express your answer in interval notation.
You can put this solution on YOUR website! The sum of the first three is 250.
For 4 the sum must be between 320 and 356, for 320/4 is 80 and 356/4 is 89
Therefore 320-250<= average <= 356-250
The score is 70 <=x<=106.
If the score can't be >100, then 100 is the upper limit. From the wording of the question, I would say 70<=x<=100
