通分
4分之3-3分之2
=9/12-8/12
=1/12
2分之1+5分之4
=5/10+8/10
=13/10
6分之13-8分之11
=39/18-22/18
=17/18
4分之5-4分之1
=1
计算下面各题,要用简便的方法。要用有过程
8分之7-9分之1-4分之3
=7/8-6/8-1/9
=1/8-1/9
=1/72
7分之6+3分之2+3分之1
=6/7+(2/3+1/3)
=6/7+1
=13/7
7分之5-14分之3+4分之1
=(10/14-3/14)+1/4
=1/2+1/4
=3/4
5分之6-8分之3-8分之5
=6/5-(3/8+5/8)
=6/5-1
=1/5