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2002 AMC 10A Problems/Problem 19

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Problem

Spot's doghouse has a regular hexagonal base that measures one yard on each side. He is tethered to a vertex with a two-yard rope. What is the area, in square yards, of the region outside of the doghouse that Spot can reach?

\text{(A)}\ 2\pi/3 \qquad \text{(B)}\ 2\pi \qquad \text{(C)}\ 5\pi/2 \qquad \text{(D)}\ 8\pi/3 \qquad \text{(E)}\ 3\pi

Solution

Part of what Spot can reach is \frac{240}{360}=\frac{2}{3} of a circle with radius 2, which gives him \frac{8\pi}{3}. He can also reach two \frac{60}{360} parts of a unit circle, which combines to give \frac{\pi}{3}. The total area is then 3\pi, which gives \boxed{\text{(E)}}.

See Also

2002 AMC 10A (ProblemsResources)
Preceded by
Problem 17
Followed by
Problem 19
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