[統計] 嘉大行銷所考古題

[vfive (哈哈)]

In a lottery game, a player selects 6 inteners out of the first 49 positive
integers. The sposor then ramdomly selects 6 out of the first 49 positive
integers. Cash prizes are given to a player who match4, 5 or 6 inteners.
Lex X equal the number of inteners selected by a player that match inteners
selectd by the sponder.
(1) State the p.d.f X
(2) Calculate the mean,variance and standard deviation X.
(3) What value of X is mostly likely to occur?
(4) On March,2005, the jackpot was worth $450,000,000. When the prize is large,
 a lot of bets are placed. Out of 25,000,000 bets that were placed,3 people
matched 6 numbers and matched 5  numbers,22187 matched 4 numbers.
Are these numbers of winners consistent with the probability model?


請問這題是二項分配嗎?

f(x)=(6Cx)P^XQ^(n-x)嗎 p=6/49 x=0.1.2.3.4.5.6

第四小題則無頭緒

謝謝~~~~

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→ a761223:不好意思，剛剛有貼一篇寫錯了，還正在想。
→ a761223:我在想，如果是不放回的話，那好像不是二項分配耶...
→ a761223:好像是超幾何分配的樣子。
→ a761223:超幾何分配的話，有其固定的函數形式跟計算平均數、變異數
→ a761223:的公式，你可以參考自己的統計用書或查資料。
→ a761223:結果有幫到你的忙嗎？ XD 不好意思我懶得去查超幾何的公式
→ a761223:第四小題是不是要代進去算看看有沒有符合次數分配？