So I have a cube that is 1X1 so the surface area of the cube will be 6 I want to know how much the surface area will be changed if I cut off the edge, the truncated cube is 5.37 sq in What I cut off will be a triangular pyramid If I find the area of each side I figure it to be 1.5 units taken off not .63 Help on how to get the .63 of how to get the answer would be great thanks