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Contests
National and Regional Contests
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MAA AMC
AMC 12/AHSME
1991 AMC 12/AHSME
16
16
Part of
1991 AMC 12/AHSME
Problems
(1)
Mean scores
Source: AHSME 1991 problem 16
10/22/2011
One hundred students at Century High School participated in the AHSME last year, and their mean score was
100
100
100
. The number of non-seniors taking the AHSME was
50
%
50\%
50%
more than the number of seniors, and the mean score of the seniors was
50
%
50\%
50%
higher than that of the non-seniors. What was the mean score of the seniors?
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100
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112.5
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120
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D
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125
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150
<span class='latex-bold'>(A)</span>\ 100\qquad<span class='latex-bold'>(B)</span>\ 112.5\qquad<span class='latex-bold'>(C)</span>\ 120\qquad<span class='latex-bold'>(D)</span>\ 125\qquad<span class='latex-bold'>(E)</span>\ 150
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112.5
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120
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125
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150
AMC