简便计算12.5×128×0.25×0.05×1.3=12.5x（8x4x4）x0.25x0.05x1.3=（12.5x8）x（0.25x4）x（0.05x4）x1.3=100x1x0.2x1.3=26
原式=12.5*8*(4*0.25)*(4*0.05)*1.3=100*1*0.2*1.3=26
