用简便方法计算 0.49÷35*0.6 420/0.8/50 44.28/0.9/401 3.24/0.4*0.35

0.49÷35*0.6
=0.49÷7÷5×0.6
=0.07÷5×0.6
=0.014×0.6
=0.0084

420/0.8/50
=420/（0.8×50）
=420÷40
=10.5

44.28/0.9/401
=44.28/3/0.3/401
=14.76/0.3/401
=492/401
.
3.24/0.4*0.35
=81/0.35
=8100/35
=162/7