Codyís brother lives on the top floor.
Marcus, Roger, and Cody took the elevator to visit Codyís brotherís room. Then they ran down 5 flights of stairs. They realized theyíd overshot their destination, so they took an elevator up 1 floor to get to Rogerís brotherís room.
From Rogerís brotherís room the three boys went down 6 flights of stairs to visit Marcusís sister. From her room they took the elevator up 4 floors, where they met Brittany and her brother getting on at his floor.
Erin and her sister walked up 2 flights from the lobby to get to Erinís sisterís room.
On what floor does each of the college students live?