口算。 0.4×0.02= 3.5+7.6= 1.23÷3= 2.4×2.5= 16÷1.6= 0.9÷0.01= 7÷0.25= 99×0.25= 12×0.4+0.4×13= 4×(1.5+0.25)=
1.3-3.79+9.7-6.21 8×0.4×12.5×2.5
19175÷59+678 36.5×1.4-8.51
()÷20-[(
14.8×6.3-6.3×6.5+8.3×3.718.1+(3-0.299÷0.23)×1
5.09-(0.09+1.23) 9.36-(4.36-3.5)