Answer:
84
Explanation:
There are 9 pieces of luggage.
We can select the first piece 9 different ways, the second piece 8 different ways, since there are only 8 pieces left. The third piece can be selected 7 different ways.
9*8*7
504
But order doesn't matter since we are taking 3 pieces.
Divide by (3*2*1)
504/6 = 84
There are 84 different combinations of luggage