Problema Solution
Teresa’s five test grades for the semester are 86%, 78%, 68%, 92%, and 72%. Her final exam counts one-third of her final grade. What range of grades on her final exam would result in Teresa receiving a final grade of B in the course? For Teresa to obtain a B in this course, her average must be greater than or equal to 80 but less than 90.
Answer provided by our tutors
If the average on the final exam counts for 1/3 of his overall grade, then the average of all the test scores already taken will count as 2/3 of his grade.
Let's first find the test average:
(86+78+68+92+72)/5 = 79.2
The test average is 79.2.
So, 2/3 of 79.2 = (2/3)(79.2) = 52.8
Let 'x' represent the result on the final exam.
80 <= 53.8 + x/3 < 90
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78.6 <= x < 108.6
To get a B in this course Teresa needs to have final exam score no less than 78.6.