Final answer:
The standard speed limit in New Jersey for a business or residential area tends to be between 25-35 miles per hour, and it's important for drivers to adhere to this limit for safety and to avoid tickets, despite the possible existence of a higher de facto speed limit.
Step-by-step explanation:
The New Jersey speed limit in a business or residential area, unless otherwise posted, is commonly set around 25-35 miles per hour.
This is a general rule that drivers must adhere to when there are no signs indicating the speed limit. In most cases, especially in residential areas, the safety of pedestrians and cyclists is a primary concern, hence the establishment of such speed limits. It is also worth noting that while the de jure (legal) speed limit might be one thing, the de facto speed limit may be slightly higher, as it's the speed that police may actually begin to ticket drivers. For instance, if the posted speed limit is 35 miles per hour, police may not pull over drivers until they exceed this limit by a certain margin. However, it's important for drivers, such as the young Peter in the scenario provided, to adhere to the legal limits to maintain safety and avoid penalties.