新北师大版四年级下册小数简便运算(共1页).doc

精选优质文档-倾情为你奉上新北师大版小学四年级下册简便运算1.加法交换结合律：4.80.251.75 57.81.432.20.57 1.288.90.72 3.572.881.43 1.292.351.711.65 3.785.270.73 16.728.93.3 0.580.390.420.611.250.753.207.53.412.536.615.839.510.58.221.970.781.530.381.621.630.321.372.682.乘法交换结合律（一）：（152.5）4=382.54=3520.5=（600.25）4=（1.255）0.8=2.5170.4=（2.512.5）（8