Question

A train that is 280 metres long, travelling at a uniform speed, crosses a platform in 60 seconds and passes a man standing on the platform in 20 seconds. What is the length of the platform in metres?

Answer 1

For a train to cross a person, it takes 20 seconds for its 280m.

So, for second 60 seconds. 

Total distance travelled should be 840. 

Including 280 train length 

so length of plates = 840 - 280 = 560