１、In an optics kit there are 6 concave lenses, 4 convex lenses, and 3 prisms. In how many ways can choose one of the concave lenses, one of the convex lenses, and one of the prisms?
２、In a small geology class, each of the 4 students must write a report on one of 8 field trips. In how many different ways can they each choose one of the field trips if
(a) no 2 students may choose the same field trip;
(b) there is no restriction on their choice?
３、In how many ordered ways can a television director schedule 6 different commercials during the 6 time slots allocated to commercials during the telecast of the first period of a hockey game?
４、Determine the number of ways in which a manufacturer can choose 2 of 15 locations for a new warehouse.
- 1 decade agoFavorite Answer
我覺得你的這些問題應該是排列組合裡的乘法原理 不知道這樣解答是否正確 參考看看吧