Answer:
75.00 km/h.
Step-by-step explanation:
Average speed of the journey = total distance / total time taken.
The first part of the journey:
60 = 20/time
60 * time = 20
time = 20/60 =
Second part: 1/3 of an hour.
90 = 30 / time
time = 30/90 = 1/3 of an hour.
So the total distance is 50 km and the total time is 2/3 hours.
Therefore the average speed
= distance / time
= 50 / 2/3
= 150/2
= 75.00 km/h.
