7/3-3/1+7/4-3/2简便计算还有12/3+13/12-13/7+12/11我晕了,

分类: 作业答案 • 2021-12-20 01:24:58

问题描述：

7/3-3/1+7/4-3/2简便计算还有12/3+13/12-13/7+12/11
我晕了,

答

化成同分母的分数做吧，

答

你写反了,呵呵.
3/7-1/3+4/7-2/3
=(3/7+4/7)-(1/3+2/3)
=1-1
=0
3/12+12/13-7/13+11/12
=(3/12+11/12)+(12/13-7/13)
=14/12+5/13
=7/6+5/13
=91/78+30/78
=121/78