看板 Statistics 關於我們 聯絡資訊
SPADES是黑桃不是紅心 P(黑桃同花|抽到四張黑桃一張非黑桃然後丟掉)= P(抽到四張黑桃丟掉非黑桃然後第五張從剩下排堆抽到黑桃) / P(抽到四張黑桃一張非黑桃然後丟掉)= 13*12*11*10*39 * 9 ------------------- 52*51*50*49*48 * 47 / 13*12*11*10*39 -------------- 52*51*50*49*48 =9/47 應該就是這麼單純 ※ 引述《agnes12 (agnes)》之銘言: : 有一題關於撲克牌的機率問題想請教: : Brenda從52張撲克牌中選五張牌,拿到四張紅心,一張非紅心。 : 她決定把那張非紅心的卡丟棄(discard), : 然後從剩下的撲克牌中再選一張卡。 : 問:Brenda最後手上有五張紅心的機率。 : 英文原文題目: : Brenda is dealt (from a well-shuffled deck) five cards. : She looks at the cards and discovers that there are four spades : in her hand, as well as one card of a different suit. : Brenda decides to discard the card of a different suit : and draw one card from the remaining cards to : complete a flush in spades (all five cards spades). : Determine the probability that she completes the flush. : 我的想法是, : 這個問題等同於問從52-5=47張牌中,抽中紅心的機率是多少?---> 9/47 : 但是又懷疑有這麼單純嗎@_@ : 想集思廣益一下,謝謝! -- ※ 發信站: 批踢踢實業坊(ptt.cc), 來自: 36.229.197.172 ※ 文章網址: https://www.ptt.cc/bbs/Statistics/M.1474271338.A.A35.html
agnes12: 哈 謝謝! 忽然發現自己中英文翻譯沒對上XD 09/19 23:13