Idaho Written Driver's License Practice Test

Why are minimum speeds posted on some freeways?

1. To ensure drivers have fun

2. Because driving too slow can impede traffic and is dangerous

3. To limit the number of cars on the freeway

4. To ensure optimal fuel efficiency

The correct answer is: Because driving too slow can impede traffic and is dangerous

Minimum speeds are posted on some freeways to enhance safety and maintain smooth traffic flow. When vehicles travel significantly below the minimum speed, it can create hazards such as sudden lane changes and collisions, as faster-moving traffic may not anticipate slower vehicles. This is particularly important on high-speed roadways, where the difference in speed can lead to dangerous situations. Ensuring that vehicles maintain a certain speed helps reduce congestion and prevent accidents caused by speed differentials among vehicles. The other options do not address the primary safety concern associated with minimum speeds. Driving at reduced speeds may not contribute to fun or fuel efficiency, nor is it an effective method for limiting the number of cars on the freeway. Therefore, the rationale for posting minimum speeds is rooted in maintaining safety and efficient traffic flow on busy roadways.