Final answer:
To find the amount of change in temperature every hour, set up the equation 5x = 12, and solve for x to find that the temperature dropped by 2.4° every hour.
Step-by-step explanation:
To find the amount of change in temperature every hour, we can set up an equation. Let x represent the amount of change. The equation would be 5x = 12. Divide both sides of the equation by 5 to solve for x. So, x = 12/5 = 2.4.
Therefore, the temperature dropped by 2.4° every hour.