A man buys an article for $20. and sells it for $25. Find the gain percent?  Answers: A) 25 % B) 50 % C) 20 % D) 15 % E) 30 %

Rationale: "c . p . = $ 20 s . p . = $ 25 gain = $ 5 gain % = 5 / 20 * 100 = 25 % answer is a"
Answer: A