Task: Question Answering
Input (English): Problem: running at their respective constant rates, machine x takes 2 days longer to produce w widgets than machine y. at these rates, if the two machines together produce 5 / 4 w widgets in 3 days, how many days would it take machine x alone to produce 3 w widgets ?
Options: a. 4, b. 6, c. 18, d. 10, e. 12
Output (English): c