Context: Three real estate companies—RealProp, Southco, and Trustcorp—are considering trading buildings with one another. Each building they own is categorized as either class 1, class 2, or class 3, depending on its approximate value: RealProp owns the Garza Tower (class 1), the Yates House (class 3), and the Zimmer House (class 3). Southco owns the Flores Tower (class 1) and the Lynch Building (class 2). Trustcorp owns the King Building, the Meyer Building, and the Ortiz Building, all of which are class 2. Each trade must be of exactly one of the following three kinds: Trading one building for one other building of the same class Trading one class 1 building for two class 2 buildings Trading one class 2 building for two class 3 buildings

Question: Which one of the following could be the buildings owned by the three companies after only one trade is made?

Answer: RealProp: the Flores Tower and the Garza Tower Southco: the Lynch Building, the Yates House, and the Zimmer House Trustcorp: the King Building, the Meyer Building, and the Ortiz Building

Answer: RealProp: the Garza Tower, the King Building, and the Ortiz Building Southco: the Flores Tower and the Lynch Building Trustcorp: the Meyer Building, the Yates House, and the Zimmer House

Answer: RealProp: the Garza Tower and the Lynch Building Southco: the Flores Tower, the Yates House, and the Zimmer House Trustcorp: the King Building, the Meyer Building, and the Ortiz Building

Answer: RealProp: the Garza Tower, the Meyer Building, and the Yates House Southco: the Flores Tower and the Lynch Building Trustcorp: the King Building, the Ortiz Building, and the Zimmer House

Answer: RealProp: the Garza Tower, the Yates House, and the Zimmer House Southco: the Lynch Building and the Ortiz Building Trustcorp: the Flores Tower, the King Building, and the Meyer Building


Question: Which one of the following CANNOT be true, no matter how many trades are made?

Answer: The buildings owned by RealProp are the Flores Tower and the Garza Tower.

Answer: The buildings owned by Southco are the Flores Tower and the Meyer Building.

Answer: The buildings owned by Southco are the Garza Tower and the Lynch Building.

Answer: The buildings owned by Trustcorp are the Flores Tower and the Ortiz Building.

Answer: The buildings owned by Trustcorp are the Garza Tower and the Meyer Building.


Question: If RealProp owns only class 2 buildings after some number of trades, which one of the following must be true?

Answer: Trustcorp owns a class 1 building.

Answer: Trustcorp owns the Meyer Building.

Answer: Southco owns a class 2 Building.

Answer: Southco owns both of the class 3 buildings.

Answer: Southco owns the Flores Tower.


Question: If Trustcorp owns no class 2 buildings after some number of trades, which one of the following must be true?

Answer: RealProp owns a class 1 building.

Answer: Southco owns only class 2 buildings.

Answer: Southco has made at least one trade with Trustcorp.

Answer: Trustcorp owns the Garza Tower.

Answer: Trustcorp owns the Zimmer House.


Question: Which one of the following CANNOT be true, no matter how many trades are made?

Answer: The buildings owned by RealProp are the Lynch Building, the Meyer Building, and the Ortiz Building.

Answer: The buildings owned by Southco are the Garza Tower and the Meyer Building.

Answer: The buildings owned by Southco are the King Building, the Meyer Building, and the Ortiz Building.

Answer: The buildings owned by Trustcorp are the Flores Tower and the Yates House.

Answer: The buildings owned by Trustcorp are the Garza Tower and the Lynch Building.