列竖式计算(带●的要验算)●754÷5=816÷8=25×18=●73×64=
8-x= 3-x=
2x+3x=3.15 3.4x=8.6-1.8
2(200-15x)=70+25x 3(2x+1)=12
0.92×1.41+0.92×8.59 ×-×1.3×11.6-1.6×1.3 ×11.6+18.4×
13×÷ 29÷×15.68+(5.39+4.32) 19.68-(2.97+9.68) 7+(-) 5-(-)