Task: Question Answering
Input (English): Problem: two trains start from p and q respectively and travel towards each other at a speed of 50 km / hr and 40 km / hr respectively . by the time they meet , the first train has traveled 100 km more than the second . the distance between p and q is ? 
Options: a ) 900 km , b ) 300 km , c ) 700 km , d ) 800 km , e ) 100 km
Output (English): a