用简便方法计算下面各题.3.8×6.7+3.3×3.8 1.28×0.29﹣0.29×0.28 101×4.8 56×12.5.
8.37﹣2.58﹣3.42.
74+16=16+74 .
96×1.02=3.96+3.96×0.02,运用了乘法分配律. .
用简便方法计算.0.25×0.5×16 0.78×2020.8×630×0.125 9.7×0.47+1.53×9.7﹣9.7.
在横线里填上合适的数9+(a+b)=( + )+ 5x+2x=( + )× (a+b)×0.5= × + × .