[Mathematics] Black and white blocks in football, black blocks are pentagons, white blocks are hexagons, and black and white are on the sphere, with a total of 12 black blocks. How many white squares are there? Suppose white skin has x blocks, then it has 6x sides. Among the 6x edges, one part is connected with white skin, and the other part is connected with black skin. Obviously, there are 3x edges connected with black skin. Solution: Let white leather * * * have X pieces, then it * * * has 6x sides, and the number of sides stitched with black leather is 3x. According to statistics, there are 12 black skins, and each black skin has 5 sides, so the black skin * * * has 5× 12=60 sides. According to the meaning, we get: 3x=60. If we solve this equation, we get x=20. So, there are 20 pieces of white skin.