3.75乘4.23乘36-125乘0.423乘2.8巧算方法
3.75*4.23*36-125*0.423*2.8
=4.23*(3.75*36-12.5*2.8)
=4.23*12.5*(0.3*36-2.8)
=4.23*12.5*8
=423
0.怎么来的;用提取公因数的方法,求高手指教,