720/15-195/15-225/15的简便运算
问题描述:
720/15-195/15-225/15的简便运算
答
720/15-195/15-225/15的简便运算
=( 720-195-225)/15
=( 720-195-225)/15
=[720-(195+225)]/15
=[720 - 420 ] /15
= 300 / 15
= 20