Unitary Method ...

A car travelling at a speed of 60 km/ hour can complete a journey in 10 hours. How long will it take to travel the same distance at 80 km/hour?

A man covers a certain distance between his house and office on a Scooter. Having an average speed of 20 km/hr, he reaches office late by 15 minutes. However, with a speed of 50 km/hr, he reaches his office 10 minutes earlier. The distance between his house and office is 

It takes 10 seconds for a train travelling at 50 km/hr to cross entirely another train half its length and travelling in opposite direction at 42 km/hr. It also passes a bridge in 41 seconds. The length of the bridge is:

Two trains travel in the same direction at 70 km/hr and 43 km/hr, respectively. A man in the slower train observes that the faster train passes him completely in 10 seconds. What is the length of the faster train in meters?

If the speed of a swimmer in still water is 11 km/h. Find the downstream speed of the swimmer, when the river is flowing with the speed of 5 km/h?

If a car travels at an average speed of 60 kilometres per hour for 3 hours, how many kilometres does it travel?

A train 250 m long is moving at a speed of 30 km/h. It will cross a man coming from the opposite direction at a speed of 6 km/h in