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CapitalSwine

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I'm stuck on this question:

'In how many ways can a committee of 3 women and 4 girls be chosen from 7 women and 6 girls so that if the eldest woman is serving on the committee then the youngest girl is not?'
 

integral95

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So you first consider the case where the eldest women is chosen, that means there's 2 other women to choose from 6 and 4 girls from 5 since one of them is out.



Then you consider the other case where the eldest women isn't chosen, that means there's 3 women from a group of 6 to choose from and a group of 4 girls from 6.



Add them both to get 375, is that the answer?
 

Roy G Biv

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alternatively, divide into 3 cases:
oldest woman in, youngest girl not
oldest woman out, younger girl in
oldest woman out, youngest girl out

you get the same answer :)
just understand what you're doing and think your way through. integral's way is 100% correct too.
 

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