五年级数学 1、用简便方法计算, (1)8.56×2.7+1.44×2.7 (2) 1.25×2.5×4×0.8(3)5.74×99+5.74 (4)72×0.03+0.3×2.82、计算下列各题.(5)9÷[(38.02+1.98)×0.5] (6)1.2×(3.2-2.99÷2.3)(7)(1.79+1.2×0.1)÷0.25 (8) 5.8÷[8×(1.8-1.3)]3.解方程.(6分)(9)5.6 X-8.6=19.4 (10) 3.2 X-1.5 X=0.51 (11)(x+0.3)÷2=7.15急~~快~~

问题描述:

五年级数学 1、用简便方法计算, (1)8.56×2.7+1.44×2.7 (2) 1.25×2.5×4×0.8
(3)5.74×99+5.74 (4)72×0.03+0.3×2.8
2、计算下列各题.
(5)9÷[(38.02+1.98)×0.5] (6)1.2×(3.2-2.99÷2.3)
(7)(1.79+1.2×0.1)÷0.25 (8) 5.8÷[8×(1.8-1.3)]
3.解方程.(6分)
(9)5.6 X-8.6=19.4 (10) 3.2 X-1.5 X=0.51 (11)(x+0.3)÷2=7.15
急~~快~~

2.7*(8.56+1.44)=2.7*10=271.25*0.8*(2.5*4)=1*10=105.74*(99+1)=5740.03*(72+28)=39/(40*0.5)=9/20=0.451.2*(3.2-1.3)=1.2*1.9=2.4-0.12=2.28(1.79+0.12)*4=7.645.8/(8*0.5)=5.8/4=1.455.6x=28    ...