When the posted speed limit is 70 mph, the minimum speed limit is __________ mph.

When the posted speed limit is 70 mph, the minimum speed limit is established at 50 mph. This means that drivers are expected to maintain a speed that is not lower than this minimum to ensure safe and efficient traffic flow. Driving significantly below this limit can create potential hazards by causing unexpected slowdowns in traffic, which can increase the risk of accidents, especially on high-speed roads. It is important for drivers to adhere to both speed limits—maximum and minimum—to maintain safety on the roadways.