2.5×2.4×0.7 =2.5×(4×0.6)×0.7 =(2.5×4)×(0.6×0.7) =10×0.42 =4.2 0.46+4.6×9.9 =4.6×0.1+4.6×9.9 =4.6×(0.1+9.9) =4.6×10 =46 1.08×0.9÷0.27 =1.08÷0.27×0.9 =4×0.9 =3.6 3.72×2.5×0.4 =3.72×(2.5×0.4) =3.72×1 =3.72