Whenever Katie and her family eat donuts, they need some coffee to dunk them in. She notices that for each donut they need 2 ounces of coffee. Every pot of coffee she makes contains 12 ounces and costs $3 to make. If her family finishes 3 dozen donuts, how much do they spend on coffee? Let's think first. Chain of thought:
He family eats 36 donuts because 3 x 12 = 36. They need 72 ounces of coffee for these because 2 x 36 = 72. This is equal to six pots of coffee because 72 / 12 = 6. This will cost $18 to make because 6 x 3 = 18.
Therefore, the answer is 18.