The length of one pair of opposite sides of a square is increased by 5 cm on each side: the ratio of the length and the breadth of the newly formed rectangle becomes 3 : 2. What is the area of the original square?

25 sq.cm.

81 sq.cm.

225 sq.cm

None of these

Correct Answer : C

The length of a rectangular hall is 5 m more than its breadth. The area of the hall is 750 m^{2}. The length of the hall is: