A man travels at 50 km/hr for 2 hours, the next at 40 km/hr for 2.5 hours and the next 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?

Correct option is A

Given:

Speed = 50 km/hr, Time = 2 hours
Speed = 40 km/hr, Time = 2.5 hours
Speed = 60 km/hr, Time = 3 hours
Formula Used:
Total distance = Speed × Time
Average speed = Total distance ÷ Total time
Solution:
Distance for first part = 50 × 2 = 100 km
Distance for second part = 40 × 2.5 = 100 km
Distance for third part = 60 × 3 = 180 km
Total distance = 100 + 100 + 180 = 380 km
Total time = 2 + 2.5 + 3 = 7.5 hours
Average speed =$$\frac{ 380}{ 7.5}$$​= 50.67 km/hr