12分之1÷9(（5分之4减2分之1) )乘6分之5
=1/12÷9(4/5-1/2)×5/6
=1/4÷(8/10-5/10)×5/6
=1/4÷3/10×5/6
=1/4×10/3×5/6
=25/36
3分之2除(1减5分之2减5分之3）
=2/3除0
=0÷2/3
=0
12分之1÷9(（5分之4减2分之1) )乘6分之5
=1/12÷9(4/5-1/2)×5/6
=1/4÷(8/10-5/10)×5/6
=1/4÷3/10×5/6
=1/4×10/3×5/6
=25/36
3分之2除(1减5分之2减5分之3）
=2/3除0
=0÷2/3
=0