Grades 11-12 Video Solutions 2023-2023_11-12

Video Transcription

Video Summary

To solve this problem of determining where the shaded face of a tetrahedral block will land again after rolling, follow these steps: Label the faces of the tetrahedron (1, 2, 3, 4), with 4 as the shaded bottom initially. As you roll the tetrahedron by rotating it around edges, different faces land on the bottom. Even without a physical model, imagine each step and the new bottom face. Begin with face 2, then 1, 3, and continue rotating until face 4 is again on the bottom. After several rotations, face 4 lands on triangle E. Thus, the answer is E.

Keywords

tetrahedron

rolling

shaded face

rotation

geometry