A man on tour travels first 160 km at 64 km/hr and the next 160 km at 80 km/hr. The average speed for the first 320 km of the tour is-

Question: A man on tour travels first 160 km at 64 km/hr and the next 160 km at 80 km/hr. The average speed for the first 320 km of the tour is-

Solution:
Total time taken = (160/64 + 160/80) hrs
= (5/2 + 2) hrs
= (5 + 4)/2 hrs
= 9/2 hrs.


Average speed = 320 × (2/9) km.hr
= 71.11 km/hr.