標題:
maths and state questions
發問:
A transportation company has 8 lorries and 10 drivers available. When it recieves 4 orders of one lorry each, how many different selections of lorries and drivers are there to meet the requests?A sample of 5 cars is selected for a destructive test from a group containing 7 small, 4 medium and 6 large cars. How... 顯示更多 A transportation company has 8 lorries and 10 drivers available. When it recieves 4 orders of one lorry each, how many different selections of lorries and drivers are there to meet the requests? A sample of 5 cars is selected for a destructive test from a group containing 7 small, 4 medium and 6 large cars. How many smaples are possible a)with no restriction? b)with 2 small, 2 medium and 1 large cars? c)with at least 1 small cars?
最佳解答:
A transportation company has 8 lorries and 10 drivers available. When it recieves 4 orders of one lorry each, how many different selections of lorries and drivers are there to meet the requests? 8C4 * 10C4 * 4! = 352800 諗法是要先知道那些車和人被選中，而被選中的人又會坐上那一部被選中的車 8C4代表8架車抽4架出來的組合方式，10C4代表10個司機抽4個出來的組合方式，這裡的排列次序是不重要的，即係抽中司機 ABCD 和 BADC 其實都是一樣的，總之是 ABCD 4個人被選中就得 8C4 * 10C4 就會出現 4個司機和4架車的組合 每一個司機去唔同的車就代表送唔同的order，所以這裡的排列次序是重要的 4! 就是四個人選4架車的排列方式 所以答案是 8C4 * 10C4 * 4! A sample of 5 cars is selected for a destructive test from a group containing 7 small, 4 medium and 6 large cars. How many smaples are possible a)with no restriction? b)with 2 small, 2 medium and 1 large cars? c)with at least 1 small cars? a 17 C 5 =6188 代表總數有17架車，抽其中5 架出來的組合方式 b. 7C2 * 4C2 * 6C1 =756 原理同part a 一樣 c. 17C5 - 10C5 =5936 at least 1 small 其實等於用 total number of ways 減 number of ways of 0 架 small 17C5 是無限制下的 total number of ways 10C5 中代表 0 架small 之中，抽5架出來的方法，10 是來自 4+6 (medium + large)
其他解答:
maths and state questions
發問:
A transportation company has 8 lorries and 10 drivers available. When it recieves 4 orders of one lorry each, how many different selections of lorries and drivers are there to meet the requests?A sample of 5 cars is selected for a destructive test from a group containing 7 small, 4 medium and 6 large cars. How... 顯示更多 A transportation company has 8 lorries and 10 drivers available. When it recieves 4 orders of one lorry each, how many different selections of lorries and drivers are there to meet the requests? A sample of 5 cars is selected for a destructive test from a group containing 7 small, 4 medium and 6 large cars. How many smaples are possible a)with no restriction? b)with 2 small, 2 medium and 1 large cars? c)with at least 1 small cars?
最佳解答:
A transportation company has 8 lorries and 10 drivers available. When it recieves 4 orders of one lorry each, how many different selections of lorries and drivers are there to meet the requests? 8C4 * 10C4 * 4! = 352800 諗法是要先知道那些車和人被選中，而被選中的人又會坐上那一部被選中的車 8C4代表8架車抽4架出來的組合方式，10C4代表10個司機抽4個出來的組合方式，這裡的排列次序是不重要的，即係抽中司機 ABCD 和 BADC 其實都是一樣的，總之是 ABCD 4個人被選中就得 8C4 * 10C4 就會出現 4個司機和4架車的組合 每一個司機去唔同的車就代表送唔同的order，所以這裡的排列次序是重要的 4! 就是四個人選4架車的排列方式 所以答案是 8C4 * 10C4 * 4! A sample of 5 cars is selected for a destructive test from a group containing 7 small, 4 medium and 6 large cars. How many smaples are possible a)with no restriction? b)with 2 small, 2 medium and 1 large cars? c)with at least 1 small cars? a 17 C 5 =6188 代表總數有17架車，抽其中5 架出來的組合方式 b. 7C2 * 4C2 * 6C1 =756 原理同part a 一樣 c. 17C5 - 10C5 =5936 at least 1 small 其實等於用 total number of ways 減 number of ways of 0 架 small 17C5 是無限制下的 total number of ways 10C5 中代表 0 架small 之中，抽5架出來的方法，10 是來自 4+6 (medium + large)
其他解答:
此文章來自奇摩知識+如有不便請留言告知
文章標籤
全站熱搜
留言列表
