Final answer:
The speed limit on a roadway outside of an urban area, unless posted, is generally known as the default speed limit. It is typically around 55 to 65 mph or 90 to 105 km/h.
Step-by-step explanation:
The speed limit on a roadway outside of an urban area, unless posted, is generally known as the default speed limit. In most cases, the default speed limit is determined by state or local laws and is set at a safe and reasonable speed for that specific area. This speed limit may vary from one jurisdiction to another, but it is typically around 55 to 65 miles per hour (mph) or 90 to 105 kilometers per hour (km/h).