4.8*13*12.5用简便方法解:运用拆分法和分配律的简便方法,原式=6x0.8x13x12.5=(6x13)x(0.8x12.5)=78x10=780
5/13x27+12x5/13=5/13x(27+12)=5/13x39=15望采纳!谢谢!
看
5/13x27+12x5/13=5/13x(27+13)=5/13x39=5x3=15