It takes a train 20 minutes to go from station A to station B. How long does it take the train to return from station B to station A?
A:The average speed of the train on the outbound route is half its speed on the inbound route
B:The distance between the stations is 10 miles
* How to decide what is outbound route and inboud route?
* Can we assume A-B is outbound and B-A is inboud route?
luckily this is DS. It wont matter that much (which is inbound which is outbound)
We know time taken for one part of the journey.
From A We know the relation between the speeds of both the parts of the journey. So we can obviously determine the time taken for second part of the journey
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