Answer:
364
Explanation:
You need to choose 1 out 14 for the first position, then 1 out of the 13 left for the second position, then 1 out the 12 left for the third position.
That gives 14 * 13 * 12 = 2184.
If order mattered, that would be the answer, but in this case, since order does not matter, the 3 positions can be filled in 3 * 2 * 1 ways = 6 ways.
2184/6 = 364