5 pairs of cartoon characters around a round table of 10 chairs
Source: Dutch NMO 2002 p4
September 21, 2019
combinatorics
Problem Statement
Five pairs of cartoon characters, Donald and Katrien Duck, Asterix and Obelix, Suske and Wiske, Tom and Jerry, Heer Bommel and Tom Poes, sit around a round table with chairs. The two members of each pair ensure that they sit next to each other. In how many different ways can the ten seats be occupied?
Two ways are different if they cannot be transferred to each other by a rotation.