To represent the situation mathematically, we can set up the equation based on the information given:
The total temperature drop is 12° over 5 hours, and this drop occurs uniformly (the same amount every hour). Therefore, we can express this as:
\[ 5x = 12 \]
Now, to solve for \( x \) (the change in temperature every hour), we will divide both sides of the equation by 5:
\[ x = \frac{12}{5} \]
Now we perform the division:
\[ x = 2.4 \]
So, the temperature decreased by 2.4° every hour.