A vehicle travels for four kilometers at a speed of 54 m/s. The vehicle then travels for two kilometers at a speed of 47 m/s. The average speed of the vehicle during the entire six-kilometer distance is
A) 51 m/s.
B) 47 m/s.
C) 48 m/s.
D) 52 m/s.

Question

Quizplus · Accepted Answer

The average speed is calculated by dividing the total distance by the total time. For the first part, time = distance/speed = 4000m / 54m/s = 74.07s. For the second part, time = 2000m / 47m/s = 42.55s. Total time = 74.07s + 42.55s = 116.62s. Total distance = 6000m. Average speed = 6000m / 116.62s = 51.45m/s, which rounds to 51 m/s.

A Vehicle Travels for Four Kilometers at a Speed of 54