Chapter 4 of 518% of exam
Speed & Conditions
Posted limits are set for ideal conditions. Arizona also sets default limits where none are posted and expects you to slow down when the road or weather is poor.
Limits when none is posted
Where no limit is posted, drive 15 mph approaching a school crosswalk, 25 mph in any business or residential district, and 55 mph on open highways. Posted limits reach 65 mph on designated highways and 75 mph on rural freeways.
Adjust to conditions
Speed limits assume good conditions, so reduce your speed on wet, snowy, or icy roads. In bad weather, double your following distance from the vehicle ahead.
Do not impede traffic
Driving too slowly can be as dangerous as driving too fast. Keep to the right and let faster traffic pass when you are moving below the normal flow.