Rajesh purchased 10 books, 30 copies, and 20 files, respectively for Rs 2000, Rs 1500, and Rs 1200 respectively from the whole sale shop. By selling each book and each copy wholesaler made a profit of x% and y%, respectively such that y=4x. Find the profit percentage by selling all the files if the cost price of each book, each copy, and each file are in the ratio 4:2:1.