Task: Question Answering
Input (English): Problem: bob wants to run a mile in the same time as his sister . if bob ’ s time for a mile is currently 10 minutes 40 seconds and his sister ’ s time is currently 5 minutes 20 seconds , by what percent does bob need to improve his time in order run a mile in the same time as his sister ? 
Options: a ) 3 % , b ) 50 % , c ) 8 % , d ) 10 % , e ) 12 %
Output (English): b