How do u calculate the the total number of combinations, given that you have n number of object and you will choose r of the objects, but x of these objects are mutually exclusive. Let x=2 for your explanations.(adsbygoogle = window.adsbygoogle || []).push({});

I kinda have an idea on how to do this, but i cant frecall an formula for the calculations.

Total number of permutations would be [tex]\frac{n!}{(n-r)!r!}[/tex] And now i have to subtract from this, the number of combinations with one of the mutually exclusive events given that the other has happened.

P.S. Maybe i should post a question to help you understand better ? ..., as my linguistic skills are not top-notch.

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# Help with permutations and combinations

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