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CasperMonday
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CasperMonday
Alright, here is my solution

\(1-\frac{1C12*1C10*1C8*1C6}{4P12}=17/33\)

But what I can't really understand is why I divide by 4P12 and not, for example by 4C12?

I have not calculated the value of the equation which you have given, but we cannot apply permutation here because the order of cards does not matter. sequence 1,2,1,4 is the same as 1,1,2,4, we just need to check the pairs ( not the sequence of cards ).

Answer is 17/33.
4 cards from different pairs can be selected in 6C4*2*2*2*2 ways.
a sequence (without order being important) of 4 cards can be selected in 12C4 ways.

Req ans will be 1 - (6C4*2*2*2*2/12C4) = 17/33.



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