an octahedron consists of two square-based pyramids glued together along their square bases to form a polyhedron with eight faces. Imagine an ant that begins at the top vertex and walks to one of the four adjacent vertices that he randomly selects and calls vertex A. From vertex A, he will then walk to one of the four adjacent vertices that he randomly selects and calls vertex B. What is the probability that vertex B will be the bottom vertex? Express your answer as a common fraction.
I'm really bad at explaining, so bare with me here.
It's always good to have an image so next time, try to find a picture. :))
But, once the ant walks to an adjacent vertice of A, there are 4 paths for the ant to take, one of the paths lead to the vertex B.
So 1/4 is our answer. :))