Question 782066: An instructor has graded 33 exam papers submitted by students in a class of 34 students, and the average so far is 65. (The maximum possible score is 100.)
A) To raise the class average by 1 point, the score on the last paper has to be what?
B) To raise the class average by 2 points, the score on the last paper has to be what?
Answer by stanbon(75887)   (Show Source):
You can put this solution on YOUR website! An instructor has graded 33 exam papers submitted by students in a class of 34 students, and the average so far is 65. (The maximum possible score is 100.)
A) To raise the class average by 1 point, the score on the last paper has to be what?
Sum of scores of the 33 graded papers:: 33*65
Score on the 34th paper:: x
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Equation:
(33*65+x)/34 = 66
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33*65 + x = 34*66
x = 99
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B) To raise the class average by 2 points, the score on the last paper has to be what?
Equation::
33*65 + x = 34*67
x = 133 (which is impossible)
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Cheers,
Stan H.
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