①8.4×0.26+0.74, =2.184+0.74, =2.924; ②23.4÷7.8-2.1, =3-2.1, =0.9; ③0.25×13.2×4, =(0.25×4)×13.2, =1×13.2, =13.2; ④2.65×1.7+13.5×0.17, =2.65×1.7+1.35×1.7, =(2.65+1.35)×1.7, =4×1.7, =6.8; ⑤0.78÷0.25×4, =3.12×4, =12.48; ⑥0.8×(3.2-3.2÷1.6), =0.8×(3.2-2), =0.8×1.2, =0.96. |