What is the prima facie speed limit for highways outside urban districts that are not numbered by the state or US?

The prima facie speed limit for highways outside urban districts that are not designated with a specific number by the state or U.S. is indeed 60 mph. This speed limit is established as a guideline intended to promote safe and efficient driving in areas that are less densely populated and generally have lower traffic volumes. The rationale behind this limit is to ensure that drivers can travel at a reasonable speed while still being mindful of safety considerations, such as road conditions and the presence of pedestrians or cyclists, which may be more common in certain areas outside urban settings.

In contrast, the other speed limits provided do not align with the established regulations for highways in these specific circumstances. A limit of 50 mph is often associated with more congested or residential areas, while 55 mph is commonly seen as a limit for certain rural roads. The 65 mph speed limit is generally designated for high-speed corridors or major highways where higher speeds can be maintained safely. Thus, the choice of 60 mph as the prima facie limit reflects the balance of safety and efficiency for highways outside urban districts.