vinod and kaurvaki start travelling in the same direction at 8 km/hr and 13 km/hr respectively. After 4 hours, vinod doubled his speed and kaurvaki reduced his speed by 1 km/hr and reached the destination together. How long did the entire journey last ?
Answers
Answer:
9 hours
Explanation:
Vinod and kaurvaki start travelling in the same direction at 8 km/hr and 13 km/hr respectively.
Speed of Vinod = 8 km/h
Speed of Kaurvaki = 13 km/h
After 4 hours distance covered by Vinod:
Distance (Vinod) = 4 x 8 = 32 km
After 4 hours distance covered by kaurvak:
Distance (kaurvak) = 4 x 13 = 52 km
New speed of Vinod (double his speed) = 16 km/h
New speed of kaurvak (reduced by 1 km/h) = 12 km/h
Now they traveled t hours to reach destination.
Distance covered by Vinod in t hours:
Distance (Vinod) = 16t
Distance covered by kaurvak in t hours:
Distance (kaurvak) = 12t
Total distance covered by both would be same.
Therefore,
Total distance covered by Vinod = Total distance covered by kaurvak
32 + 16t = 52 + 12t
16t -12t = 52 - 32
4t = 20
t = 5 hours
Total time time = 4+5 = 9 hours
Hence, The entire journey was last in 9 hours.