Hans is staying at a hotel that has five floors, numbered 1 through 5, and 10 rooms per floor, numbered 1 through 10. Hans forgets where his room is, but knows that it is on an odd numbered floor and the room nujmber is divisible by 3. If Hans randomly choose a room he knows might be his room, what is the probability that Hans chooses the correct room? Express your answer as a common fraction.
There is three odd floors. 1, 3, and 5. There are three rooms per floor that are divisable by 3: 3, 6, and 9. The total number of rooms that Hans can choose from is: 3 possible floors times 3 possible rooms equals 9 choices. The probability that Hans picked the correct room is \(p=\frac{1}{9}\).