用简便方法做(12/5-7/3)-(7/4-12/7)=

问题描述:

用简便方法做(12/5-7/3)-(7/4-12/7)=

(12/5-7/3)-(7/4-12/7)
=12/5-7/3-7/4+12/7
=(12/5+12/7)-(7/3+7/4)
=1-1
=0