A man on a journey goes 160 kilometres at 64 kilometres per hour and 160 kilometres at 80 kilometres per hour. For the first 320 kilometres of the tour, the average speed is:
A. 35.55 km/hr
B. 36 km/hr
C. 71.11 km/hr
D. 71 km/hr
Answer:C
A man on a journey goes 160 kilometres at 64 kilometres per hour and 160 kilometres at 80 kilometres per hour. For the first 320 kilometres of the tour, the average speed is:
A. 35.55 km/hr B. 36 km/hr C. 71.11 km/hr D. 71 km/hr
Explanation: Total time required = 160/64 + 160/80 hrs = 9/2 hrs.320 x 2/9 km/hr = 71.11 km/hr average speed.