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

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

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

Thanks bobbym

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

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

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

Thanks bobbym got it

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

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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