arithmetic - two trains running in opposite directions cross a man standing on the platform in 27 seconds and 17 seconds respectively and they cross each other in 23 seconds the ratio of their speeds is - skillgun

Let the speeds of the two trains be x m/sec and y m/sec respectively.
Then, length of the first train = 27x metres,
Length of the second train = 17y metres.
[because distance = speed*time]
27x+17y/x+y=23=>27x+17y=23x+23y=>4x=6y=>xy=64
So ratio of the speeds of train is 3:2