Q. What is the average speed of the car in a travel of 180Km
1) The car travelled 1st 120Km at 60Km/hr average speed
2) The car travelled last 120Km at 60Km/hr average speed
Average speed = Total distance / Total time
We have total distance, but not total time.
We have total distance, but only a part of the time.
We have total distance and total time. Sufficient.
Answer is C.