2023 AMC 12A Problems/Problem 21
Problem
If 
and 
are vertices of a polyhedron, define the 
C to be the minimum number of edges of the polyhedron one must traverse in order to connect and . For example, if AB is an edge of the polyhedron, then 
= 1, but if AC and CB are edges and AB is not an edge, then = 2. Let Q, R, and S be randomly chosen distinct vertices of a regular icosahedron (regular polyhedron made up of 20 equilateral triangles). What is the probability that 
?
Solution 1
See also
| 2023 AMC 12A (Problems • Answer Key • Resources) | |
| Preceded by First Problem |
Followed by Problem 22 |
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| All AMC 12 Problems and Solutions | |
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