25秋五年级上册数学小数简便计算题 3.25×0.45+6.75×0.45 =0.45×(3.25+6.75) =0.45×10 =4.5 2.15+8.73+1.27+7.85 =(2.15+7.85)+(8.73+1.27) =10+10 =20 11.87﹣(8.2+1.87) =11.87﹣1.87﹣8.2 =10﹣8.2 =1.8 4.38﹣1.56+0.62﹣0.44 =(4.38+0.62)﹣(1.56+0.44) =5﹣2 =3 0.4×270×2.5 =(0.4×2.5)×270 =270 (40+1.25)×8 =40×8+1.25×8 =320+10 =330