12.5x32=12.5x8x4=100x4=400
12.5×32的简便方法:12.5×32=12.5×8×4=100×4=400
运用乘法分配律计算可得,12.5×(30+2)=12.5×30+12.5×2=375+25=400
(12.5*8)*4=100*4=400
32 =12.5x8x4 =100x4 =400