2349 /www/nrich/html/content/04/weekly/prob25/ 1 2010-11-12T18:01:37 <?xml version="1.0" encoding="UTF-8"?> <mdoxml version="1.0"></mdoxml> <?xml version="1.0" encoding="UTF-8"?> <mdoxml version="1.0"> <p>For the triangular faces of the resulting solid to be equilateral it is necessary for the tetrahedra cut from each corner to be regular. Removing a regular tetrahedron from each corner will not change the total length of all the edges. Therefore, as the original solid has 6 edges of length 6cm, the total length of all the edges is 36cm.</p> </mdoxml> <?xml version="1.0" encoding="UTF-8"?> <mdoxml version="1.0"> <p>For the triangular faces of the resulting solid to be equilateral it is necessary for the tetrahedra cut from each corner to be regular. Removing a regular tetrahedron from each corner will not change the total length of all the edges. Therefore, as the original solid has 6 edges of length 6cm, the total length of all the edges is 36cm.</p> </mdoxml> 2 3 0 0 0 0 0 Weekly Problem 2 - 2012 ajk44 Alison's problems under development