把3.4.0.5组成三位数,奇数(),偶数(),3的倍数(),5的倍数(),既是2的...答:405,403,435,453,305,345,503,543; 340,304,350,354,540,504,534,530,430,450; 345,354,435,453,534,543,504,540,405,450; 340,350,430,450,530,540,345,305,435,405; 450,540
用3、4、5、6这4个数字组成四位数,每个数字在同一个数中最多只能使用2...答:②由3个数字组成的:(i)由3,4,5组成:重复数字是3的:3345,3354,3435,3453,3534,3543,4335,4353,4533,5334,5343,5433:共12个。重复数字是4的也是12个。重复数字是5的:3455,3545,3554,4355,4535,4553,5345,5354,5435,5453:共10个。此类34个。(ii)仿上,由346组成的有30个。由356...