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2011 AMC 10B Problem 20

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2011 AMC 10B Problem 20AMC 10 Step by Step

Name: Date: September 13, 2026

Quadrilaterals & Polygon Areas · difficulty 3 of 5 · about 5 min · position P16-20

Rhombus $ABCD$ has side length $2$ and $\angle B = 120^\circ$ . Region $R$ consists of all points inside the rhombus that are closer to vertex $B$ than any of the other three vertices. What is the area of $R$ ?

A)
$\frac{\sqrt{3}}{3}$
B)
$\frac{\sqrt{3}}{2}$
C)
$\frac{2\sqrt{3}}{3}$
D)
$1 + \frac{\sqrt{3}}{3}$
E)
$2$

2011 AMC 10B Problem 20

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