During a five-hour period, the temperature steadily dropped 20F. By how many degrees did the temperature change each hour?

Question

 (Use negative (-) sign to show a drop in temperature)

Answer 1

The temperature drops 20 degrees in 5 hours. To find out how much the temperature drops per hour, simply divide the total temperature change by the number of hours.

 

Hence:

-20 degrees / 5 hours = -4 degrees per hour

 

Another way to think about this is algebraically. We can set up the problem this way.

 

-20 degrees = 5 hours * x, where x is the change in temperature per hour. Solving for x leads to the equation above.