(1) [(0.05+
=[(0.05+0.25)÷0.25-40%]×
=[0.3÷0.25-40%]×
=[1.2-0.4]×
=0.8×
=0.1; (2) [4
=[4
=[4
=[4
=0×0.125, =0; (3) 6.4×1.3+1÷
=6.4×1.3+1×1.3+1.3×2.6, =(6.4+1+2.6)×1.3, =10×1.3, =13; (4) 7.4×
=7.4×1.25+1.25×2.5+1.25×0.1, =(7.4+2.5+0.1)×1.25, =10×1.25, =12.5. |