To solve this question, we need to determine the number of surfaces of the solid when a second pyramid is removed from the cube.
Initially, we have a cube with side length of 2 units, which means:
1. The total number of surfaces of a cube is 6.
After removing the first pyramid from one side of the cube:
- The pyramid has a square base with the same dimension as the cube’s face (2x2) and a height of 1 unit.
- Upon removal, 4 triangular faces of the pyramid become exposed.
- Thus, the original face of the cube where the pyramid was removed is replaced with these 4 triangular faces.
- As a result, after the first removal, we have an additional triangular face.
This gives a total of 9 surfaces: 5 remaining cube faces + 4 triangular pyramid faces.
When the second pyramid with the same dimensions is removed from another face of the solid, consider:
- The new pyramid removal exposes 4 more triangular faces on another original cube face.
- One triangular face from each pyramid will meet at the edge of the cube (since cube's original edge length equals the pyramid base edge length), forming a single surface instead of two separate ones.
- This results in one less surface compared to if they did not meet.
Counting all surfaces:
- Originally 6 cube faces
- Minus 2 cube faces where pyramids are removed = 4
- Plus 8 triangular faces from two sets of removed pyramids
- Minus 2 for the meeting edge surfaces = 10 total surfaces
Therefore, the resultant solid after removing the second pyramid will have 10 surfaces.