错1、5.7×10.2=5.7×10+5.7×0.2=58.14(运算错
错2、2.9×8×1.25=2.9×(8×1.25)(运用了乘法结合律
错3、0.25×9.9=0.25×10—0.25×0.1 =2.5-0.025=2.475
错4、3.2×2.5×12.5=(0.4×2.5)×(8×12.5)
对5、0.3×0.4=0.2×0.6
错1、5.7×10.2=5.7×10+5.7×0.2=58.14(运算错
错2、2.9×8×1.25=2.9×(8×1.25)(运用了乘法结合律
错3、0.25×9.9=0.25×10—0.25×0.1 =2.5-0.025=2.475
错4、3.2×2.5×12.5=(0.4×2.5)×(8×12.5)
对5、0.3×0.4=0.2×0.6