A bus travels for three hours at 60 km/h, four hours at 50 km/h and the next five hours at 50 km/h. Find its average speed,
Show answer & explanation
Correct answer: A
Explanation
The correct answer is option 1 i.e. 52.5 km/h.
Average speed = Total distance/Total time
According to the given question,
Distance travelled in 3 hours = 3 × 60 = 180 km
Distance travelled in next 4 hours = 4 × 50 = 200 km
Distance travelled in last 5 hours = 5 × 50 = 250 km
Average speed = (180 + 200 + 250)/(3 + 4 + 5)
⇒ 630/12 = 52.5 km/h