In covering a distance of 72 km, Amit takes 5 hours more than Vinay. If Amit doubles his speed, then he would take 7 hours less than Vinay. Amit's speed is:
3 km/h
Let the speed of Amit be x km/h. Then, the time taken by Amit to cover the distance is 72/x hours. Let the speed of Vinay be y km/h, so the time taken by Vinay is 72/y hours. According to the given conditions, we get the equations: 1) 72/x = 72/y + 5 2) 72/(2x) = 72/y - 7. Solving these equations, we find that x = 3 km/h.
Important Questions from Speed Time and Distance
A train travelling at a speed of 72 km/hr crosses a post in 20 seconds. If it crosses another train travelling at a speed of 54 km/hr in the same direction in 1 minute 45 seconds, then the difference in length between the two trains is
Rajiv's boat can travel along the current at the 8 km/hour and against the current at the rate 6 km/hour. Find the time taken by the boat to sail 28 km in still water.
Rohit and Dinesh are 64 km apart. Rohit can walk at a speed of 15 km/hr and Dinesh at the speed of 17 km/hr. In how many hours will they meet if they are travelling towards each other?
Two trains running in opposite directions cross a man standing on the platform in 25 seconds and 32 seconds respectively and they cross each other in 30 seconds. The ratio of their speed is:
A worker covers a distance of 81 km in 11 hours. He travels partly on foot at 4.5 km/h and partly on bicycle at 15 km/h. What is the distance covered on the cycle?
