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Joined: 21 Sep 2012
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Concentration: Operations, General Management
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Re: What is the number of 7-element subsets of the set {1, 2, 3, 4, 5, 6,
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16 Mar 2020, 09:48
In this question, we have to form 3 element subsets from {0,2,4,6,8}.
It will be same as selecting 3 elements from the given elements.
But in the question, there is additional condition mentioned that the subset should contain 6 but it should not contain 8.
Now, we need to definitely select 6 (1C1 ways) and select two elements from 0, 2, 4 (3C2 ways).
So, total number of ways will come out to be 1C1 × 3C2 = 3 ways.