Emily and Holly took a road trip together. Emily drove at an average of 45 miles per hour for the first 3/7 of the total distance, and Holly drove the last 24 miles at an average rate of 54 miles per

Emily and Holly took a road trip together. Emily drove at an average of 45 miles per hour for the first 3/7 of the total distance, and Holly drove the last 24 miles at an average rate of 54 miles per hour. How long did the trip take the two of them? Give your answer in terms of hours.