2001 AMC 12 Problem 10
Below is the professionally curated solution for Problem 10 of the 2001 AMC 12, from LIVE by Po-Shen Loh. You can also try the full timed exam, view all 2001 AMC 12 solutions, or check the answer key.
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Difficulty rating: 1480
10.
The plane is tiled by congruent squares and congruent pentagons as indicated. The percent of the plane that is enclosed by the pentagons is closest to
Solution:
The pattern repeats over a block of nine unit squares. Four of these nine squares are not covered by pentagons; the rest of the area belongs to the pentagons.
So the pentagons enclose which is closest to
Thus, the correct answer is D.
Problem 10 in Other Years
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