A travels for 8 hours at the rate of 4 km/h and for 4 hours at the rate of 8 km/h. The average speed of the journey (in km/h) is:
Show answer & explanation
Correct answer: B
Explanation
The correct answer is option 2 i.e. .
To find the average speed, we need to calculate the total distance traveled and the total time taken.
Total distance:
⇒ Distance traveled at 4 km/h = 8 hours × 4 km/h = 32 km
⇒ Distance traveled at 8 km/h = 4 hours × 8 km/h = 32 km
⇒ Total distance = 32 km + 32 km = 64 km
Total time:
⇒ Total time = 8 hours + 4 hours = 12 hours
Average speed:
⇒ Average speed = Total distance / Total time
⇒ Average speed = 64 km / 12 hours ≈ 5.33 km/h
Therefore, the average speed of the journey is approximately 5.33 km/h.