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by frumpychic » Wed Nov 02, 2011 7:26 am
From a group of 20 people, what is the ratio of the different teams of 4 that can be selected to the different groups of 5 people teams that can be selected?
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by shankar.ashwin » Wed Nov 02, 2011 7:32 am
5 people teams possible;

20C5 * 15C5 * 10C5 * 5C5 / 4!

4 people teams possible;

20C4 * 16C4 * 12C4 * 8C4 * 4C4 / 5!.

You need to find ratio between both.
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by neelgandham » Wed Nov 02, 2011 7:37 am
[spoiler]5/16 [/spoiler] ?
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by shankar.ashwin » Wed Nov 02, 2011 7:48 am
Is it just 20C5/20C4? I was assuming all 20 people be formed into teams of 5 and 4. That would be way too big a number..
neelgandham wrote:[spoiler]5/16 [/spoiler] ?
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by frumpychic » Wed Nov 02, 2011 7:49 am
why is it not 20C4/20C5 ?
Last edited by frumpychic on Wed Nov 02, 2011 8:00 am, edited 1 time in total.
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by GmatMathPro » Wed Nov 02, 2011 7:53 am
I think it's 20C4/20C5=[spoiler]5/16[/spoiler]
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by neelgandham » Wed Nov 02, 2011 8:01 am
shankar.ashwin wrote:Is it just 20C5/20C4? I was assuming all 20 people be formed into teams of 5 and 4. That would be way too big a number..
neelgandham wrote:[spoiler]5/16 [/spoiler] ?
I don't think the question asked the total number of ways in which 20 people can be arranged in 5 teams of 4 each. It just said 'different teams of 4'
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