On the Convocation Day of a college, 3500 students assembled in the auditorium, and sat in rows of 175 students each. How many rows were formed?
In a school auditorium, the number of chairs in a row is the same as the number of rows of chairs. There are 7033 students in the school. If we know that less than 31 chairs were empty, how many chairs were empty after all the students sat down?