5/7-6/13×5/7=5/7X(1-6/13)=5/7X7/13=5/13=13分之5
=5/7(1_6/13)=5/7X7/13=5/13
5/7-6/13×5/7怎么样简便运算5/7-6/13×5/7=5/7×(1-6/13)=5/7×7/13=5/13