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#1 2012-12-17 02:19:48

jacks
Member
Registered: 2012-11-21
Posts: 80

probability

Two no. are selected from the set

without replacement one by one .

Then the probability that minimum of 2 no. is

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#2 2012-12-17 02:42:16

bobbym
Administrator
From: Bumpkinland
Registered: 2009-04-12
Posts: 86,676

Re: probability

Hi jacks;

Fairly simple to just enumerate:

If I draw a six, I have 3 numbers to pick, same for a 5 and a 4. So that is 3 * 3 = 9

If I draw a 3, I have 5 numbers to pick, same with 2 and 1. So 3 * 5 = 15.

Probability is 4 / 5.


In mathematics, you don't understand things. You just get used to them.
Of course that result can be rigorously obtained, but who cares?
Combinatorics is Algebra and Algebra is Combinatorics.

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#3 2012-12-17 02:45:39

jacks
Member
Registered: 2012-11-21
Posts: 80

Re: probability

Thanks bobbym

But I did not understand the meaning of minimum of 2 no. is < 4 (whta does it mean)

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#4 2012-12-17 02:57:01

bobbym
Administrator
From: Bumpkinland
Registered: 2009-04-12
Posts: 86,676

Re: probability

Say you pick a 6 and then a 4, remember without replacement means no two numbers are the same.

The minimum of a 6 and a 4 is 4. It means the smallest value out of the two numbers picked.


In mathematics, you don't understand things. You just get used to them.
Of course that result can be rigorously obtained, but who cares?
Combinatorics is Algebra and Algebra is Combinatorics.

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#5 2012-12-17 03:00:02

jacks
Member
Registered: 2012-11-21
Posts: 80

Re: probability

Thanks bobbym got it

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#6 2012-12-17 03:02:47

bobbym
Administrator
From: Bumpkinland
Registered: 2009-04-12
Posts: 86,676

Re: probability

Okay, you are welcome.


In mathematics, you don't understand things. You just get used to them.
Of course that result can be rigorously obtained, but who cares?
Combinatorics is Algebra and Algebra is Combinatorics.

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