A shopkeeper sold an article at $100 with 30% profit. Then find its cost price?  Select the correct option:	A) $ 120	B) $ 100	C) $ 91	D) $ 77	E) $ 69

Rationale: "cost price = selling price * 100 / ( 100 + profit ) c . p . = 100 * 100 / 130 = $ 77 ( approximately ) answer is d"
Answer: D