分析:悄孙 (1)依据整顷改数四则运算计算顺序解答, (2)依据除法性质解答, (3)(5)(6)运用乘法分配律解答, (4)化44=4×11解答. (1)2400÷80+14×12, =30+168, =198; (2)420÷[(205-198)×4], =420÷[7×4], =420÷7÷4, =60÷4, =15; (3)63×73-63×63, =63×(73-63), =63×10, =630; (4)启乎链25×44, =25×4×11, =100×11, =1100; (5)57×19+57, =57×(19+1), =57×20, =1140; (6)85×(100+1), =85×100+85×1, =8500+85, =8585. 点评: 本题主要考查学生依据四则运算计算方法,以及正确运用简便算法解决问题的能力,注意计算的顺序.