MathDB
Problems
Contests
National and Regional Contests
USA Contests
MAA AMC
AMC 8
2009 AMC 8
8
8
Part of
2009 AMC 8
Problems
(1)
Rectangle Scaling
Source:
11/26/2009
The length of a rectangle is increased by
10
%
10\%
10%
and the width is decreased by
10
%
10\%
10%
. What percent of the old area is the new area?
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A
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90
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B
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99
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C
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100
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D
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101
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E
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110
<span class='latex-bold'>(A)</span>\ 90 \qquad <span class='latex-bold'>(B)</span>\ 99 \qquad <span class='latex-bold'>(C)</span>\ 100 \qquad <span class='latex-bold'>(D)</span>\ 101 \qquad <span class='latex-bold'>(E)</span>\ 110
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(
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90
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(
B
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<
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99
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C
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<
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100
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D
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<
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101
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E
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<
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110
geometry
rectangle
percent