Danielle's apartment has 6 rooms. Heidi's apartment has 3 times as many rooms as Danielle's apartment. Grant's apartment has 1/9 as many rooms as Heidi's apartment. How many rooms does Grant's apartment have? Let's think first. Chain of thought:
Heidi's apartment has 6 * 3 = 18 rooms. Grant's apartment has 18 / 9 = 2 rooms.
Therefore, the answer is 2.