作者Arfeo (閃)
看板Math
標題[機統] 抽籤的期望值?
時間Mon May 2 10:08:20 2011
欸..想問一下機率的問題
下面是我在其他課本中看到的敘述:
... the expected number of draws required to draw one red ball out of a
bin containing n red balls and N-n grenn balls is (N+1)/(n+1)
if the balls are not replaced.
想問一下這是怎麼推出來的QQ
謝謝:)
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◆ From: 140.115.210.76
1F：→ Arfeo :少打 if the balls are not replaced ..XD 05/02 10:09
2F：推 sa12e3 :按大E修改! 05/02 10:10
※ 編輯: Arfeo 來自: 140.115.210.76 (05/02 11:10)