update: *edit: solved! I counted everything twice. 1. The problem statement, all variables and given/known data How many ways are there to seat 10 people, consisting of 5 couples, in a row of seats (10 seats wide) if all couples are to get adjacent seats? 3. The attempt at a solution I'm trying to look calculate it at a couple level. 10 seats available, 5 couples _ _ _ _ _ _ _ _ _ _ first couple has 9 choices to choose from They can't choose seat # 10 or else they will not sit next to each other. they can also swap seats, so that will be 9 x 2 = 18 choices. second couple will have 7 seats to choose from. They can trade seats, so that will be 7 x 2 = 14 third couple has 5 seats, trade seats an yield 10. fourth couple has 3 seats, = 6 5th couple has 2 seats left, they can trade once, so that is 2 possibilities I did 18 x 14 x 10 x 6 x 2 = 30,240. answer key says 3840 though?