Task: Question Answering
Input (English): Problem: three pipes a, b and c can fill a tank from empty to full in 30 minutes, 20 minutes and 10 minutes respectively. when the tank is empty, all the three pipes are opened. a, b and c discharge chemical solutions p, q and r respectively. what is the proportion of solution p in the liquid in the tank after 3 minutes ?
Options: a. 3 / 11, b. 2 / 11, c. 1 / 11, d. 4 / 11, e. 1 / 11
Output (English): b