Task: Question Answering
Input (English): Problem: a takes twice as much time as b & c takes thrice as much time as b to finish a piece of work . working together they can finish the work in 18 days . the no . of days need for b to do the work alone is ? 
Options: a ) 30 days , b ) 31 days , c ) 33 days , d ) 41 days , e ) 52 days
Output (English): c