The range of a dataset is the difference between the highest value in the data and the lowest value.
We know the highest value of the temperature in a city was 69°F and the lowest was -26°F.
The range is the difference of these values:
Range = 69°F - (-26°F)
The subtraction becomes a sum because of the product of two minus signs:
Range = 69°F + 26°F = 95°F