Degree days are the difference between the daily temperature mean, (high temperature plus low temperature divided by two) and 65°F. 65°F because we assume that at this temperature we do not need cooling or heating. In our case the daily mean temperature is 83°F and X is the number of cooling-degree days. X=83-65 X=18
The daily mean temperature in a particular place is 83. how many cooling-degree days were accumulated?