Thread: Combinatorics QUESTION 1-3

Nine chairs in a row are to be occupied by six students and three professors. The three
professors arrive before the six students and decide to choose their chairs so that each
professor will be between two students. In how many ways can the professors choose their
chairs?

Originally Posted by maximus101

Nine chairs in a row are to be occupied by six students and three professors. The three
professors arrive before the six students and decide to choose their chairs so that each
professor will be between two students. In how many ways can the professors choose their chairs?

You have posted problems without any comment whatsoever.
Do you expect someone to do them for you?