128
555
6 ways
20 of the 3 legged stools and 11 of the 4 legged chairs
4 people seated on a row may have 4! = 4x3x2x1 = 24 different ways to sit.
24
128
555
8x7x6x5x4= 6720
5 chairs x 5 people = 25 choices
All I know is that each person can sit on a chair. There aren't many ways with the details you said. There might be 2 chairs with 2 people on each chair. There really only is one way.
Six.
Usually people sit on chairs. Some Synagogues may have benches to sit on.
chairs
Close to 150
There are about 2 sensible reasons. You get 25 chairs tell the 25 people to sit. Tell them to sit on the floor.Answer:25 people can be seated in 25! ways (25! is factorial 25, or 25x24x22x21 ....x3x2x1) as the first chair can be filled in 25 ways, the second in 24, the third in 23 and so on. This comes to 1.5511210043 × 1025 different ways
12