Net of the truncated body

The solid (pyramid) is cut by the horizontal plane z = 6.2. Find the net of the remaining body.

Step-by-step solution

Find the section of the solid by the cutting plane.
Unfold the trimmed lateral faces, the base and the top (the section in true shape).
Check that the net does not overlap and that the perimeter of the top matches the upper edge.
If the plane does not cut the body, there is no truncated body.

Result: net with 6 pieces; surface 47.97 u².

The top of the truncated body is the section in true shape: if you do not rotate it flat, the net is wrong.