A pipe can fill a cistern in 18 minutes whereas the cistern when fill can be emptied by a leak in 36 minutes. When both pipes are opened, find when the cistern will be full?\nOptions:\n(A) 17\n(B) 36\n(C) 70\n(D) 13\n(E) 12 Stream of consciousness:
User
1/18 - 1/36 = 1/36\n36 minutes
Thus, the answer is (B).
Assistant