4 children out of 8 will be selected. But two oldest children can not be both chosen. Total number of combinations = ?(adsbygoogle = window.adsbygoogle || []).push({});

The mutually exclusive situations are really confusing me.

I know if they were independent, total n. of combinations would be

[tex]\frac{8!}{(8-4)!4!}=70[/tex]

I need to subtract the total number of combinations with one of the two oldest boys. I am at a dead end, even though i feel like i know how to do it. My mind kinda went blank.

PS. This is the last question i need to answer to finish my "beutifully done" homework. help :P I have high expectations from this piece of art.

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# Homework Help: Perms and Combs

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