12.5x0.69x8的简便方法:12.5x0.69x8=12.5×8×0.69=100×0.69=69
12.5*8*0.69=12.5*2*4*0.69=25*4*0.69=100*0.69=69
12.5×0.69×8=(12.5×8)×0.69=100×0.69=69
原式=12.5×8×0.69=100×0.69=69
12.5×0.69×8=12.5×8×0.69=100×0.69=69