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- Mysterious loss of weight 17 answers
A man goes into a room and sits down.
Suddenly his weight increases, then eventually resumes back to normal.
After several hours - suddenly his weight decreases, then eventually resumes back to normal.
Finally when the man exits the room, his weight is the same as when he went in.
EDIT: The answer is not "He went in an elevator".
What transpired was not an abnormal event.