SOLUTION: to earn a B in a course, you must have a final average of 84%. On the first three examinations, you have grades of 80%, 72%, and 86%. if the final examination counts as two grades,
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-> SOLUTION: to earn a B in a course, you must have a final average of 84%. On the first three examinations, you have grades of 80%, 72%, and 86%. if the final examination counts as two grades,
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Question 1004876: to earn a B in a course, you must have a final average of 84%. On the first three examinations, you have grades of 80%, 72%, and 86%. if the final examination counts as two grades, what must you get on the final to get a B on the course? Answer by addingup(3677) (Show Source):
You can put this solution on YOUR website! We'll call the final grade x. Since it equals two grades: 2x
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(80+72+86+2x)/5= 84
(238+2x)/5= 84 Multiply both sides times 5 (the magical rule of "do no harm" in equations, always do to one side what you do to the other):
238+2x= 420 Subtract 238 from both sides:
2x= 182
x= 91
