Task: Question Answering
Input (English): Problem: kavi had a stock of 600 bags in his bookshop . he sold 25 on monday , 70 on tuesday , 100 on wednesday , 110 on thursday and 145 on friday . what percentage of the bags were not sold ? 
Options: a ) 10 % , b ) 25 % , c ) 64 % , d ) 42 % , e ) 17 %
Output (English): b