2009 AMC 8 Problem 8
Below is the professionally curated solution for Problem 8 of the 2009 AMC 8, from LIVE by Po-Shen Loh. You can also try the full timed exam, view all 2009 AMC 8 solutions, or check the answer key.
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Difficulty rating: 920
8.
The length of a rectangle is increased by and the width is decreased by . What percent of the old area is the new area?
Solution:
Let the old length and width be and , so the old area is .
The new length is , and the new width is . Thus the new area is .
This shows that the new area is of the old area.
Thus, B is the correct answer.
Problem 8 in Other Years
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