用简便方法计算. 4300÷4÷25 1456-237-763 125x32x25 99×999 89×99+89 268-(168-35)
(1)4300÷4÷25 =4300÷(4×25) =4300÷100 =43; (2)1456-237-763 =1456-(237+763) =1456-1000 =456; (3)125×32×25 =125×8×4×25 =(125×8)×(4×25) =1000×100 =100000; (4)99×999 =99×(1000-1) =99×1000-99×1 =99000-99 =98901; (5)89×99+89 =89×(99+1) =89×100 =8900; (6)268-(168-35) =268-168-35 =100-35 =65. |