A regular icosahedron is a three-dimensional solid composed of twenty

[BTGModeratorVI]

A regular icosahedron is a three-dimensional solid composed of twenty equilateral triangular faces, with five faces meeting at each vertex. How many vertices does a regular icosahedron have?

A. 5
B. 12
C. 20
D. 33
E. 60

Answer: B
Source: Veritas Prep

[Brent@GMATPrepNow]

A regular icosahedron is a three-dimensional solid composed of twenty equilateral triangular faces, with five faces meeting at each vertex. How many vertices does a regular icosahedron have?

A. 5
B. 12
C. 20
D. 33
E. 60

Answer: B
Source: Veritas Prep

Each triangle has 3 vertices, and there are 20 triangles in total.
So, the total number of triangle vertices = 3 x 20 = 60

Each vertex in the icosahedron is comprised of five triangle faces meeting at a point.
In other words, it takes 5 triangle vertices to make 1 icosahedron vertex .
We have 60 triangle vertices, so the TOTAL number of icosahedron vertices = 60/5 = 12

Answer: B

Cheers,
Brent