A train travels the first 200 km of a journey at a speed of 100 km/h and the remaining 150 km at a speed of 75 km/h. What is the average speed (in km/h) of the train for the entire journey?
Show answer & explanation
Correct answer: B
Explanation
The correct answer is option 2 i.e. 87.5.
⇒ Total distance = 200 + 150 = 350 km
⇒ Total time = 200 ÷ 100 + 150 ÷ 75 = 2 + 2 = 4 hours
⇒ Average speed = 350 ÷ 4 = 87.5 km/h