作者starsky822 (豆漿)
看板Statistics
標題[問題] 機率問題求解
時間Tue Oct 23 23:54:50 2012
如果是跟統計軟體有關請重發文章
如果跟論文有關也煩請您重發文章
文章類別是為了幫助大家搜尋資料與解答，造成不便之處請見諒
老師要求解出上課時的習題，但又不是很了解@@"
問題1
In a particular community, 70% of the voters are Democrats, and 30% are
Republicans. Thirty percent of the Republican voters and 60% of the
Democratic voters favor the incumbent. What is the probability that a
randomly selected voter from this community is a Republican who favors the
incumbent?
問2
The frequency of twin births has been increasing in recent years so that in
2000 about 3% of all births were twins. Twins may be either identical or
fraternal. The probability of a birth being that of identical twins has
remained fairly constant at 0.4%. What proportion of twin births is identical?
在此求助各位的幫忙，先謝謝各位了!!!
感謝!!!
--
※ 發信站: 批踢踢實業坊(ptt.cc)
◆ From: 111.252.178.19
1F：推 goshfju:Q1. 貝氏機率 畫下樹枝圖就出來了 10/24 02:26
2F：推 goshfju:Q2. 比較像在考英文.. 0.4%/3% = =? 10/24 02:29
3F：→ starsky822:好，感謝g大，問2原來是我翻譯有問題XD 10/24 08:17