笔算下面各题,并按要求验算.286+54= 40÷8= 880﹣407=验算:900﹣273= 52÷6= 634+189=验算:
合理、灵活地计算 32×61.9+38.1×32 25×16×50×0.13×[0.75﹣(﹣)](1﹣)÷[(0.1+1.1)÷0.2].
(1)(2) (3)(4).
计算 (1)+9+999+9999(2)4(2) (3)351(4)(111+999).
4.85÷﹣3.6+6.15×3.
(1)16×(+0.125)(2)3×7+6.25÷ (3)1111×37+9999×7(4)36÷()