標題:
統計學問題.....有點難...
發問:
In a certain community, 36% of the families own a dog and 22% of the families thatown a dog also own a cat. In addition, 30% of the families own a cat. What is(a) the probability that a randomly selected family owns both a dog and a cat;(b) the conditional probability that a randomly selected family owns a... 顯示更多 In a certain community, 36% of the families own a dog and 22% of the families that own a dog also own a cat. In addition, 30% of the families own a cat. What is (a) the probability that a randomly selected family owns both a dog and a cat; (b) the conditional probability that a randomly selected family owns a dog given that it owns a cat? thx for ur ans
此文章來自奇摩知識+如有不便請留言告知
最佳解答:
Let C be the event that a randomly selected family owns a cat Let D be the event that a randomly selected family owns a dog Pr (C) = 0.3 Pr (D) = 0.36 Pr (C AND D) = 0.22 a) Pr (C AND D) = 0.22 b) Pr (D | C) = Pr (C AND D) / Pr (C) = 0.22 / 0.3 = 11 / 15
其他解答:
(a) P(dog and cat) = 36% x 22% = 7.92% (b) P(dog | cat) = P(dog and cat) / P(cat) = 7.92% / 30% = 26.4% =
留言列表
