- #1
Ryoukomaru
- 55
- 0
4 children out of 8 will be selected. But two oldest children can not be both chosen. Total number of combinations = ?
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.![Big Grin :biggrin: :biggrin:](data:image/gif;base64,R0lGODlhAQABAIAAAAAAAP///yH5BAEAAAAALAAAAAABAAEAAAIBRAA7)
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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