Task: Question Answering
Input (English): Problem: a ’ s speed is 25 / 18 times that of b . if a and b run a race , what part of the length of the race should a give b as a head start , so that the race ends in a dead heat ? 
Options: a ) 1 / 18 , b ) 7 / 18 , c ) 7 / 25 , d ) 3 / 25 , e ) 1 / 25
Output (English): c