# A Carpenter's Tetradecahedron

Geometry Level 3

The artistic carpenter forms a tetradecahedron from a cube with side length 3". For each of the cube's vertices, he measures an inch out on the edges, and cuts out the resulting right tetrahedron from each corner, leaving 6 octagonal faces, and 8 triangular faces. The volume is $$\frac{a}{b}$$ where $$a$$ and $$b$$ are relatively prime positive integers and the surface area is $$c+d\sqrt{e}$$, and $$e$$ is prime. What is the sum $$a+b+c+d+e$$?

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