Cedar and Asa took a trip together to visit their father. When they arrived, their father asked them how long the trip had taken. Cedar said that she had driven the first 450 miles, which represents of the total distance, and Asa had driven the rest. Asa said the average speed for the trip was 45 miles per hour. If they stopped for 30 minutes to eat lunch, what was the answer to their father's question? (Include the lunch time in the total travel time.)