GMAT Problem Solving (PS) | Re: If exactly 3 of the following 5 letters - A,B,B,C,C – are chosen to

Responding to a pm:

Actually, while picking the type of letters, some enumeration will be required.

The 3 letter chosen could be all distinct or 2 could be identical and 1 different. All 3 identical are not possible since there is no letter available thrice.

All 3 distinct: There is only 1 way of selecting
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