SOLUTION: The average (arithmetic mean) of the test scores of a class of "p" students is 70, and the average of the test scores of a class of "n" students is 92. When the scores of both clas

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Question 197888: The average (arithmetic mean) of the test scores of a class of "p" students is 70, and the average of the test scores of a class of "n" students is 92. When the scores of both classes are combined the aveage is 86. What is the value of p / n?
Answer by stanbon(75887) About Me  (Show Source):
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The average (arithmetic mean) of the test scores of a class of "p" students is 70,
Total # of points for these p students is 70p
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And the average of the test scores of a class of "n" students is 92.
Total # of points for these n students is 92n
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When the scores of both classes are combined the aveage is 86.
Total # of points for the combined classes is 86(n+p)
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What is the value of p / n?
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Equation:
Grand total points = Grand total points
70p + 92n = 86(n+p)
70p + 92n = 86n + 86p
16p = 6n
p/n = 6/16
p/n = 3/8
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Cheers,
Stan H.