Task: Question Answering
Input (English): Problem: bookman purchased 40 copies of a new book released recently , 10 of which are hardback and sold for $ 20 each , and rest are paperback and sold for $ 10 each . if 14 copies were sold and the total value of the remaining books was 300 , how many paperback copies were sold ? 
Options: a ) 6 , b ) 4 , c ) 8 , d ) 10 , e ) 12
Output (English): c