Why can you divide 0/5 but not 5/0? Saburou Saitoh Saburou Saitoh Edit Credential Very and very surprisingly enough, you are right; indeed, 0/5=5/0!! Please look our new results on the division by zero. They are elementary and fundamental mathematics. 23] viXra:1909.0517 submitted on 2019-09-24 16:12:58, (68 unique-IP downloads) What Was Division by Zero?; Division by Zero Calculus and New World (Compact Version)