2009 AMC 8 Problems/Problem 8

Revision as of 14:52, 14 August 2021 by Raina0708 (talk | contribs) (Solution)

Problem

The length of a rectangle is increased by $10\%$ percent and the width is decreased by $10\%$ percent. What percent of the old area is the new area?


$\textbf{(A)}\  90  \qquad \textbf{(B)}\   99  \qquad \textbf{(C)}\   100  \qquad \textbf{(D)}\   101  \qquad \textbf{(E)}\   110$

Solution

In a rectangle with dimensions 10*10 the new rectangle would have dimensions 11*9 The ratio of the new area to the old area is 99/100 =99

See Also

2009 AMC 8 (ProblemsAnswer KeyResources)
Preceded by
Problem 7
Followed by
Problem 9
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All AJHSME/AMC 8 Problems and Solutions

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