Answer: 54.54 mph
Step-by-step explanation: To calculate the average speed of a car that traveled 300 miles in 5.5 hours, you can divide the total distance traveled by the total time taken: Average speed = Total distance / Total time-average speed = 300 miles / 5.5 hours = 54.55 miles per hour (mph)So, the average speed of the car is 54.55 mph.