Task: Question Answering
Input (English): Problem: a and b can complete a work in 15 days and 10 day . they started doing the work together but after 2 days b had to leave and a alone completed the remaining work . the whole work was completed in ? 
Options: a ) 10 days , b ) 12 days , c ) 15 days , d ) 8 days , e ) 16 days
Output (English): b