SOLUTION: Students in Math 120 must have both a passing overall average of at least 70% and a grade of at least 70% on the final to pass the class. Bob has a quiz average of 70%, and three e

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Question 262774: Students in Math 120 must have both a passing overall average of at least 70% and a grade of at least 70% on the final to pass the class. Bob has a quiz average of 70%, and three exam grades of 54%, 66% and 76%. If the quiz average counts the same as an exam and the final counts as two exam grades, what range of grades on the final will permit Bob to pass the class?... to earn a B(80
Answer by drk(1908) About Me  (Show Source):
You can put this solution on YOUR website!
quiz average = 70
exam grades = 54, 66, 76
exam total = 196
exam average = 65.333
Quiz = exam
final = 2*exam
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70 < Q + ex + F
70 < (70 + 65.333 + 2E)/4
280 < 135.333 + 2E
144.666 < 2E
77.333 < E
you need 78% or better to pass class
--
we have
80 < Q + ex + F< 90
80 < (70 + 65.333 + 2E)/4 < 90
320 < 135.333 + 2E < 360
184.666 < 2E < 224.666
92.333 < E < 112.333
you need 93% or better to get a B.