A shopkeeper sold an article at $100 with 45% profit. Then find its cost price?  Choose the correct choice from the following choices.
A) $ 120 B) $ 100 C) $ 91 D) $ 72 E) $ 69

Rationale: "cost price = selling price * 100 / ( 100 + profit ) c . p . = 100 * 100 / 145 = $ 69 ( approximately ) answer is e"
Answer: E