A 3-minute lesson from the Michigan course. Read the rules and examples, follow the handbook page references, and check your understanding before you move on.
Posted limits are maximums, not targets. Michigan's Basic Speed Law says your speed must fit the conditions, and state law sets default limits for places where no sign is posted.
Basic Speed Law
Drive at a "careful and prudent" speed for conditions, always able to stop within the clear distance ahead. Never faster than the posted limit; sometimes slower.
Watch for posted limits in business districts, county, state and federal parks, on roads next to parks and playgrounds, and in school and hospital zones — these limits vary.
It's foggy on a freeway posted 70 mph and you can see only a short distance ahead. The Basic Speed Law requires you to slow to a speed that lets you stop within that clear distance — even well below 70.
Put it into practice
On an unposted rural two-lane highway (not a freeway), the limit is 55 mph.
Check your understanding
Read the question, decide on an answer, then open it to check the explanation. These are Roadwise study questions based on the source handbook.
What does Michigan's Basic Speed Law require, regardless of the posted limit?
At the posted limit whenever roads are dry
At the speed most other drivers are going
Always 5 mph below the posted limit
A careful and prudent speed for conditions
Answer: A careful and prudent speed for conditions
The Basic Speed Law requires a careful and prudent speed that lets you stop within the clear distance ahead; it is never faster than posted and may be slower.