Probability問題

oscar

現在有5個連續位子，有3男2女，他們亂坐的，問問2女坐在一起的機會率是什麼？

There are 5 continuous seats now. 3 boys and 2 girls are going to sit on them at random. Find the probability that the 2 girls sit together.

比超仔

i only know 48* 100%
                   ---
                   ???

[ Last edited by 比超仔 on 2004-12-24 at 07:06 PM ]

oscar

比超仔  在 2004-12-24 19:05 發表:

i only know 48* 100%
                   ---
                   ???

即係點嘛？
都係搵落雷攪...

比超仔

我數出來
if they are ab345,ab is the girl
ab345 ba345 3ab45
ab354 ba354 3ab54
ab543 ba543 4ab35
ab534 ba534 4ab53
ab435 ba435 .....總共48個組合
ab453 ba453

抹茶可樂

Total possible outcomes =5!=5x4x3x2x1=120

Consider the combination "OOXXX",(O is girl, X is boy)
there are 2! x 3! = 2x1 x 3x2x1=12
Similarly we get "XOOXX','XXOOX','XXXOO',
favourable possible outcomes =12 x 4 =48

P=48/120=2/5

Note: We considered five people aren't identical above.
We can also let two girls are same,
but is not favour to HKCEE markers or "weak" teachers.


送多條問題俾大家玩玩

如某條四選一的MC有64%的人答中，在所有答中本題的人中，
估計撞中的百分比。

[ Last edited by 落雷 on 2004-12-24 at 09:28 PM ]

oscar

嘩...好勁...
請受小弟一拜！
我-->:em46: :em23:<--落雷

莫邪

唉
觀察唔到點計
老了...?

whale273

oscar  在 2004-12-25 12:39 AM 發表:

嘩...好勁...
請受小弟一拜！
我-->:em46: :em23:<--落雷

落雷中幾??

lookge

oscar  在 2004-12-24 06:16 PM 發表:

現在有5個連續位子，有3男2女，他們亂坐的，問問2女坐在一起的機會率是什麼？

There are 5 continuous seats now. 3 boys and 2 girls are going to sit on them at random. Find the probability that the 2  ...

係0%

男女男女男<~~~重唔係0%==

抹茶可樂

whale273  在 2004-12-25 09:29 AM 發表:

落雷中幾??

Ｓ.４

lookge  在 2004-12-25 10:11 AM 發表:

係0%

男[color=49 ...

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