On each of 7 Mondays, it rained 1.5 centimeters. On each of 9 Tuesdays it rained 2.5 centimeters. How many more centimeters did it rain on Tuesdays than Mondays? Let's think first. Chain of thought:
Mondays: 7 * 1.5 = 10.5. Tuesdays: 9 * 2.5 = 22.5. 22.5 - 10.5 = 12 cm. It rained 12 centimeters more on Tuesdays than on Mondays.
Therefore, the answer is 12.