A trader bought a car at 20% discount on its original price. He sold it at a 50% increase on the price he bought it. What percent of profit did he make on the original price?	Choose the correct choice from the following:
A) 17 %  B) 72 %  C) 20 %  D) 82 %  E) 16 %

Rationale: "original price = 100 cp = 80 s = 80 * ( 150 / 100 ) = 120 100 - 120 = 20 % answer : c"
Answer: C