0.58×0.9+5.8×0.01=5.8×0.09+5.8×0.01=5.8×(0.09+0.01)=5.8×0.1=0.58
=0.58×0.9+0.58×0.1=0.58×(0.9+0.1)=0.58×1=0.58
