计算下面各题(能简便的用简便方法计算).10.15-10.75×0.4-5.75.8×(3.87-0.13)+4.2×3.7432.52-(6+9.728)÷3.2×2.5[(7.1-5.6)×0.9-1.15]÷2.55.4÷[2.6×(3.7-2.9)+0.62][20-(90.75÷6.6+2.25)]×11.6.
(1)10.15-10.75×0.4-5.7, =10.15-4.3-5.7, =10.15-(4.3+5.7), =10.15-10, =0.15; (2)5.8×(3.87-0.13)+4.2×3.74, =5.8×3.74+4.2×3.74, =(5.8+4.2)×3.74, =10×3.74, =37.4; (3)32.52-(6+9.728)÷3.2×2.5, =32.52-15.728÷3.2×2.5, =32.52-4.915×2.5, =32.52-12.2875, =20.2325; (4)[(7.1-5.6)×0.9-1.15]÷2.5, =[1.5×0.9-1.15]÷2.5, =[1.35-1.15]÷2.5, =0.2÷2.5, =0.08; (5)5.4÷[2.6×(3.7-2.9)+0.62], =5.4÷[2.6×0.8+0.62], =5.4÷[2.08+0.62], =5.4÷2.7, =2; (6)[20-(90.75÷6.6+2.25)]×11.6, =[20-(13.75+2.25)]×11.6, =[20-16]×11.6, =4×11.6, =46.4. |