A book store bought copies of a new book by a popular author, in anticipation of robust sales. The store bought \(400\) copies from their supplier, each copy at wholesale price \(W.\) The store sold the first \(150\) copies in the first week at \(80\%\) more than \(W,\) and then over the next month, sold \(100\) more at \(20\%\) more than \(W.\) Finally, to clear shelf space, the store sold the remaining copies to a bargain retailer at \(40\%\) less than \(W.\) What was the bookstore’s net percent profit or loss on the entire lot of \(400\) books?

(A) \(30\%\) loss
(B) \(10\%\) loss
(C) \(10\%\) profit
(D) \(20\%\) profit
(E) \(60\%\) profit

Answer: D

Source: Magoosh