Prob.

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Prob.

by marouan » Fri Feb 06, 2009 5:26 am
Hi All, easy but I stuck on it !
A certain compagny employs 6 senior officers and 4 junior officers. If a comitee is to be created that is made up of 3 senior officers and 1 junior officer, How many different committees are possible?

* 8
* 24
* 58
* 80 ( That was the right answer )
* 210

Thanks
Last edited by marouan on Fri Feb 06, 2009 8:30 am, edited 1 time in total.

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by Uri » Fri Feb 06, 2009 5:32 am
It seems the problem is not reproduced correctly.
You can select 6 senior officers from 6 senior officers in only 1 way. And you can pick 1 junior officer from 4 junior officers in 4 ways. For each of the way that you pick a junior officer, you have only one combination of senior officers. So, the total combination will be 4*1 = 4.

Am I missing any point?

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by mrsmarthi » Fri Feb 06, 2009 5:33 am
I think there might be some mistake in the question. If not then the number of ways a committe can be formed with 6Seniors and 1 Junior is 4 ways.

This is becuase, for each combination, all the 6 Senior will be picked. And amoung 4 Juniors, there are 4 ways we can pick one junior.

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by gaggleofgirls » Fri Feb 06, 2009 8:23 am
Given that the right answer is 80, I am guessing that the correct question is a committee of 3 senior officers and 1 junior officer.

That would be 6c3 * 4c1 = 20*4 = 80.

-Carrie

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by marouan » Fri Feb 06, 2009 8:33 am
My bad..
yeah it's of 3 senior out of 6 and 1 jenior
And yeah gaggleofgirls you got it: it's a comnbination..
Thanks every body.. and Im realy realy sorry for teh mistake !
Thx All!
All the best