If the length of a rectangle is halved and its breadth is tripled, what is the percentage change in its area?  Choose the correct choice:
A) 30
B) 40
C) 50
D) 60
E) 70

Rationale: length is halved . i . e . , length is decreased by 50 % breadth is tripled i . e . , breadth is increased by 200 % formula for change in area is : = ( - x + y - xy / 100 ) % = ( − 50 + 200 − 50 × 200 / 100 ) % = 50 % i . e . , area is increased by 50 % answer is c .
Answer: C