The first and sixth floors of a building belong to water. Floors whose ending numbers are one or six are also water, such as the eleventh floor, the twenty-first floor, the thirty-first floor, etc.
The second and seventh floors belong to the south and belong to fire. Therefore, the second and seventh floors of a building belong to fire, and the floors whose endings are two or seven also belong to fire, such as the twelfth floor, twenty-second floor, thirty-second floor, etc.
The third and eighth floors belong to the east and belong to wood. Therefore, the third and eighth floors of a building belong to wood, and the floors whose endings are three or eight are also wood, such as the thirteenth floor, the twenty-third floor, the thirty-third floor, and so on.
The fourth and ninth floors belong to the west and belong to gold. Therefore, the fourth and ninth floors of a building belong to gold, and the floors whose endings are four or nine are also metal, such as the fourteenth floor, the twenty-fourth floor, the thirty-fourth floor, and so on.
The fifth and tenth floors belong to the center and belong to earth. Therefore, the fifth and tenth floors of a building belong to earth. Floors whose ending numbers are five or ten also belong to earth, such as the fifteenth floor, the twenty-fifth floor, the thirty-fifth floor, etc.