One night a certain hotel rented 3/5 of its rooms, including 2/3 of their air conditioned rooms. If 3/5 of its rooms were air conditioned, what percent of the rooms that were not rented were air conditioned?
Choices: A) 50% B) 55% C) 60% D) 65% E) 70%
The rooms which were not rented is 2/5   The 50%C rooms which were not rented is (1/3)*(3/5) = 1/5   The percentage of unrented rooms which were 50%C rooms is (1/5) / (2/5) = 1/2 = 50%   The answer is 50%.
<result>A</result>
One night a certain hotel rented 3/5 of its rooms, including 2/3 of their air conditioned rooms. If 3/5 of its rooms were air conditioned, what percent of the rooms that were not rented were air conditioned?