In which format are angles expressed as decimal degrees?

The question pertains to the representation of angles in decimal degrees. Decimal degrees express angles purely in one unit, which is degrees with a fractional component that represents parts of a degree. This format simplifies calculations and is widely used in various applications, particularly in geographic information systems (GIS) where precise location data is crucial.

The correct answer involves recognizing that angles in decimal degrees do not have subdivisions like minutes and seconds, which are part of a traditional degrees and minutes format. Unlike degrees and minutes (where a degree can be divided into 60 minutes, and each minute into 60 seconds), decimal degrees provide a more straightforward representation.

In addition, radians is a completely different measurement system based on the radius of a circle, while hours and minutes relate to time rather than angular measurement. Fractional degrees, although similar to decimal degrees, do not strictly adhere to the format of expressing angles as decimal fractions, as they often imply a mixed number or a division of degrees rather than presenting the angle in a simple decimal format.

Thus, decimal degrees is a single, unified scale not partitioned into smaller units and serves as the most coherent choice for expressing angles in a straightforward numeric format.