1.4×2.5-1.95÷0.65 1.7×0.8×1.25 2.5×7.3＋1.7×2.5＋2.5 27×9.9 急
问题描述：
1.4×2.5-1.95÷0.65 1.7×0.8×1.25 2.5×7.3＋1.7×2.5＋2.5 27×9.9
急
答
1.4×2.5-1.95÷0.65=0.7×(2×2.5)-(0.39×5)÷(0.13×5)=3.5-(0.39÷0.13)=0.5
1.7×0.8×1.25=1.7×（0.8×1.25）=1.7×1=1.7
2.5×7.3＋1.7×2.5＋2.5 =2.5×（7.3＋1.7＋1）=25
27×9.9=27×(10-0.1)=27×10-0.1×27=270-2.7=267.3
答
1.4×2.5-1.95÷0.65 =(1+0.4)*2.5-1.95*100/65=1*2.5+0.4*2.5+3=2.5+1+3=6.51.7×0.8×1.25 =1.7*(0.8*1.25)=1.7*1=1.72.5×7.3＋1.7×2.5＋2.5 =2.5*(7.3+1.7+1)=2.5*10=2527×9.9 =27*(10-0.1)=27*10-27*0.1=270-...