选号要求:字母AT顺序不变,三个数字可以选6或8,尾数必须为数字,进行排列 有多少种组合?分别是?例如:A8T88
å æ好AãTï¼å ±æC(4ï¼2)=6ï¼ç§ï¼
åææ°åï¼æ2Ã2Ã2=8ï¼ç§ï¼
æ以ï¼å ±æ6Ã8=48ï¼ç§ï¼
ææ³å¦ä¸
AT666ãAT668ãAT686ãAT688ãAT866ãAT868ãAT886ãAT888ã
A6T66ãA6T68ãA6T86ãA6T88ãA8T66ãA8T68ãA8T86ãA8T88ã
A66T6ãA66T8ãA68T6ãA68T8ãA86T6ãA86T8ãA88T6ãA88T8ã
6AT66ã6AT68ã6AT86ã6AT88ã8AT66ã8AT68ã8AT86ã8AT88ã
6A6T6ã6A6T8ã6A8T6ã6A8T8ã8A6T6ã8A6T8ã8A8T6ã8A8T8ã
66AT6ã66AT8ã68AT6ã68AT8ã86AT6ã86AT8ã88AT6ã88AT8