I believe you combine the first and last terms first because they have the same denominator
Answer:
18.9
Step-by-step explanation:
The total travelled for the first five hours eould be 450 km and divided by three leaves 150 km per 1/5 of his journey. travelling at 75 km per hour, it would take 4 hours to get through the remaining 300 km for him trip leaving a total time of 9 hours of traveling