Answer:
The average car is around 14.7 feet or 4500 mm
One of them is roads and parking lots as most builders consider the length of an average car that will use such a facility. Some construction design like the parking lot planners also takes note of the kind cars and their respective sizes before making recommendations.
Different cars come in various measurements, but to get the average size of a car, you should get as many lengths as possible and determine the mean size of a vehicle.
