Page 83 - NUMINO Challenge_D1

Type 9-2 Numbers of Faces, Edges, and Vertices

One corner section is cut out from each cube, as shown below. Find
the number of faces, edges, and vertices for each solid figure
obtained.

The corner section that is cut The section that is cut out passes
out passes through the midpoints of through 3 non-adjacent vertices.

3 edges of the cube.

1 Find the number of faces, edges, and vertices of the cube.

2 If the colored part shown on the right is cut out, the number
of faces increases by 1. How do the numbers of edges and
vertices change?

3 A corner section of the cube is cut across a plane that passes through the
midpoints of 3 edges of a cube. How many faces, edges, and vertices are
in the solid figure obtained?

4 Compare the drawing on the right with a cube. Even if the
colored part is cut out, the number of edges does not
change. How do the numbers of faces and vertices change?

5 A solid figure is obtained by cutting across a plane that passes through 3
non-adjacent vertices of a cube. Find the number of faces, edges, and
vertices of the solid figure.

80 NUMINO Challenge D1