As the title, how can I solve this problem?
Should I use combination with repitition or something else different?
Any help would be appreciated
3 people are distinguish. Below here is an example of symmetry situation which only consider as 1 way
but this situation is 2 ways
Due to the rotation invariance, person $p_1$ can sit anywhere. Then $p_2$ can be one seat away from $p_1$, or two or three. Due to symmetry invariance, we can suppose that it is to the right of $p_1$. For each of these 3 options, person $p_3$ has 4 possible seats, but in the case where $p_2$ is 3 seats away from $p_1$, the positions of $p_3$ come in symmetric pairs. Hence there are $2\times 4 + 2 = 10$ ways to arrange the 3 people.