Riddle: There are five sisters in a room. All five of them are busy. Ann is reading, Rose is cooking, Lorraine is playing chess and Mary is doing laundry. What is the fifth sister doing?
Answer: In the beginning, there are five sisters in a room, they said there were a total of 5 sisters in the room.
Then they stated that all five of them were busy. So we understand that all five sisters are busy in this sentence.
Finally Ann reads, Rose cooks, Lorraine plays chess and Mary does the laundry. Now we know what the 4 sisters are doing and we have to try to find out what the fifth brother is doing.
As you can see, Lorraine is mentioned playing chess, and we all know Chess is a two-player strategy game played on a checkered board. So we can assume that the fifth sister is playing chess with Lorraine.
Therefore, the Fifth Sister is playing chess, is the answer to the Five Sisters in a Room Riddle.