Task: Question Answering
Input (English): Problem: a can do a job in 9 days and b can do it in 27 days. a and b working together will finish twice the amount of work in - - - - - - - days ?
Options: a. 22 days, b. 18 days, c. 22 6 / 2 days, d. 27 days, e. 9 days
Output (English): b