getzgetzu
If 6 people are to be divided to 3 different groups, each of which has 2 people. How many such groups are possible?
Forming first group C(6,2) = 15
Forming second group C(4,2) = 6
Forming third group C(2,2) = 1.
Number of ways of forming 3 groups = 90.
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The answer changes if the groups are named groups. Say, we have 3 groups, Reps, Dems and Inds. Since any group of 2 can be assigned to any named group, we have 6 more ways of doing that.
Then number of ways = 540.
Btw I think the question "How many such groups are possible" has a simple answer : 3. You already mentioned that we divide 6 people into 3 groups