Task: Question Answering
Input (English): Problem: a man purchased 3 blankets @ rs . 100 each , 5 blankets @ rs . 150 each and two blankets at a certain rate which is now slipped off from his memory . but he remembers that the average price of the blankets was rs . 140 . find the unknown rate of two blankets ? 
Options: a ) 350 , b ) 550 , c ) 490 , d ) 450 , e ) 457
Output (English): a