3.6÷0.18-1.25×0.8
=20-1
=19
1÷(1-3/4)
=1÷1/4
=1×4
=4
5÷(1/5)-(1/5)×75
=5×5-15
=25-15
=10
这几道题都不用简便算法,按运算法则一步一步来