A man travels at 50 km/hr for 2 hours, then at 40 km/hr for 2.5 hours, and finally at 60 km/hr for 3 hours. What is his average speed (in km/hr, rounded off to two decimal places) for the whole journey?
Show answer & explanation
Correct answer: A
Explanation
The correct answer is option 1 i.e. 50.67.
⇒ Total distance = 50 × 2 + 40 × 2.5 + 60 × 3
⇒ 100 + 100 + 180 = 380 km
⇒ Total time = 2 + 2.5 + 3 = 7.5 hours
⇒ Average speed = 380 ÷ 7.5 ≈ 50.67 km/h