On a track of length 100km, the train covers first 20km with a constant speed 30km/hr. What should be the speed of the train for the next 70km so that the average speed of the train remains 50km/hr for the entire trip?
1 Answer
May 8, 2018
Explanation:
From
- first
#20# km =#"20 km"/"30 km/hr" = 2/3\ "hr"# - next
#70# km =#"70 km"/"v km/hr" = 70/"v"\ "hr"#