Answer
20
Work Step by Step
Since the order of the individuals is important, so we use permutation.
We select 3 of the 5 people:
$$^5P_3=\frac{5!}{(5-3)!}=\frac{5!}{2!}=60.$$
Now each possible seating has 3 possible arrangements associated with it.
( because let say the chosen individuals are ${a_1, a_2, a_3}$, then in a circle, arrangement ${a_1 a_2 a_3}$ is same as ${a_2 a_3 a_1}$ and ${a_3 a_1 a_2}$)
So such type of arrangements have been counted trice.
Therefore, answer = $\frac{60}{3}=20.$
