1.口算下列各题5＋ = 72－=－= ＋16 =12－ =24－=＋ =4- =＋10= ＋4= 14－ =9－=＋9=＋ =＋12= ＋32=＋ =＋ =＋16=＋16 =＋ =＋0= ＋= ＋12=＋ = 45× =9×= × = ×100=18× =× =17× =5 × =× = ×12=×0=× = × =×12=× = 45× = 9×= × = ×100=18× =× = 17× =5 × =× = ×12= × = 45× = 9×= × =×100= 18× =× =17× =5 × = ×32=× =× =×16= ×16 =× = 5× =72×=×=×16 =12× = 24× =× = 4×=×10=×4=14× =9×=×9=45× =9×=× = ×100=18× = × =17× = 5 × = × = ×12= ×0= × = ×12=×0=× = ×12=× = 45× =9×= × =×100= 18× =× =17× =5 × = × =×12= × =45× =9×=× =×12=× = 45× =9×= × = ×100= 18× = × =6.5×5 6.5= 1×0.85= 4.73×3.9=47.3×3.9= 47.3×0.391=0.473×0.39=2.4×5＝1×1.25＝ 0.45×0.09＝6.2×0.03＝ 0.125×0.125＝9.9×2.5×0.4＝9×0.18＝0.25×16＝ 0.7×8＝3.05×4＝ 6.8×2＝5.2×3.05×4.8＝47.3×0.391= 0.473×0.39=0.45×0.09＝ 6.2×0.03＝×12= ×0= 0.77×1.1=1.2-0.08= 8- 0.52= 2.5× 3.6 = 4. 9.4×6= 5.0.8×0.92= 1.3×0.4＝5.43×0.86=78.58×3.7=0.85×1.01 =9×2.3=0.1×0.01 = 0.28×35=4.68×4.5=0.25×0.5=2.5×1.25= 25.7×3.29=6.71×25.7=8- 0.52= 2.5× 3.6 = 0.45×0.09＝6.2×0.03＝1.05×0.1＝17.5×7.5×2＝5.5×11＝1.6×0.5=2.5×0.4=0.36×0.9=1.25×8=1.6×0.4=0.48×4=0.9×0.6=13.2+4.8= 6.3-0.9= 0.25×2.4=3×1.03=＋9= ＋32= ＋ =＋ =2.5×0.4=0.36×0.9=1.3×0.4＝5.43×0.86=＋16=＋16 =＋ =5＋ = 72－=－=＋16 =12－ =24－=＋ =4-=＋9=＋ = ＋12= ＋0=＋9=＋32= ＋10=＋4=14－ =9－=＋9=＋ = ＋12=＋0= ＋=＋12= ＋ = 45× =×100=18× =× =17× = 5 × = × = ×12=×0= 9×= × =× =×12= × =45× =9×=× =×100=18× = × =17× = 5 × =×32= ×16=×16 =× =5× = 72×=×=×16 =12× =× =× =24× =× =4×=×10=×4=14× =9×= ×9= × =×12=×0=× = ×12=× =45× =9×= × =×100= 18× = × =17× =5 × = ×4=×12=×16 =×100= 1÷4=10÷5= 7...
