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Question: 2019 Winter Midterm - 8

Author: Michiel Smid
Let $n \geq 4$ be an integer. What does $$ 3 \cdot { n\choose 3} + 6n \cdot {n \choose 2} + n^3 $$ count?
(a)
The number of ways to choose 3 elements (with repetitions allowed) in a set consisting of $n$ beer bottles, $n$ cider bottles, and $n$ wine bottles.
(b)
The number of ways to choose a 3-element subset of a set consisting of $n$ beer bottles, $n$ cider bottles, and $n$ wine bottles.
(c)
The number of ways to choose an ordered triple <p style="text-align: center; margin: 0.5rem 0;"> (beer bottle, cider bottle, wine bottle) </p> in a set consisting of $n$ beer bottles, $n$ cider bottles, and $n$ wine bottles.
(d)
None of the above.