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2011 AMC 10A Problem 20

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2011 AMC 10A Problem 20AMC 10 Step by Step

Name: Date: September 13, 2026

Geometric Probability · difficulty 4 of 5 · about 5 min · position P16-20

Two points on the circumference of a circle of radius $r$ are selected independently and at random. From each point a chord of length $r$ is drawn in a clockwise direction. What is the probability that the two chords intersect?

A)
$\frac{1}{6}$
B)
$\frac{1}{5}$
C)
$\frac{1}{4}$
D)
$\frac{1}{3}$
E)
$\frac{1}{2}$

2011 AMC 10A Problem 20

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