Krystiana owns an apartment building

Krystiana owns an apartment building. The rooms on the first floor cost $15 per month and the rooms on the 2nd floor cost $20 per month. The rooms on the third floor cost twice as much as the rooms on the first floor, but only two rooms are occupied. If each floor has 3 rooms, how much does Krystiana earn every month?

GSM8K — Grade School Math 8K (Cobbe et al., OpenAI, 2021) · train #6143