口算.30÷3= 14×5= 28×4= 43+207= 2×600= 450÷5=2400÷8= 4800÷6= 800÷4= 870﹣250= 120+200= 0÷9=
1.25×8÷1.25×8= == (1.01﹣0.91)×15== ==
直接写得数.= 100÷0.01= = 1.01×0.8=1.25×0.3×8= = = =
直接写得数576﹣(4.32+1.3) ÷0.125 ÷1 0.25×1 ÷3×40﹣10÷3 1﹣+ 2.7÷ +÷ 1999×(1﹣﹣﹣0.625)
直接写得数1.6×12.5= = = 3.9×10%= == = = = 25÷25%=
口算.2.2+3.57= 1.4﹣0.6= 3.25×4= 15×= 44÷== 2﹣= ÷2= = =.