agree,forgot that

来源: atom9 于 2004-01-17 21:57:00 [档案] [旧帖] [给我悄悄话] 阅读数 : (183 bytes)

回答: Equilateral Triangle 由 yma16 于 2004-01-17 09:52:00

coin can fall through in a tilted way. If we match one altitude of the triangle coin with one side of the triangle hole when falling through, then the coin length should be 2/sqrt(3).