In how many different ways (relative to each other) can 8 friends sit around a square table with 2 seats on each side of the table?
A) 2 * 8!
B) 2 * 7!
We can take this square as a circle but with one difference....
first, if it were a circle , the ways would be 7!..
now only difference is in each arrangement of 7!, any particular person would be sitting with two different person on an edge of the table
that is he would be sitting with the person on his left on one side of the square and with the one on his right in the next arrangement without shifting relatively to each other..
so we multiply each arrangement with 2.. ans 7!*2