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2021 AMC Fall 10B Problem 21

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2021 AMC Fall 10B Problem 21AMC 10 Step by Step

Name: Date: September 13, 2026

Basic Counting · difficulty 4 of 5 · about 5 min · position P21-25

Regular polygons with $5,6,7,$ and $8$ sides are inscribed in the same circle. No two of the polygons share a vertex, and no three of their sides intersect at a common point. At how many points inside the circle do two of their sides intersect?

A)
$52$
B)
$56$
C)
$60$
D)
$64$
E)
$68$

2021 AMC Fall 10B Problem 21

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