# i tried to answer this question myself but i couldn't.i would like to get a detailed explanation. Two trains started from point A and B in opposite direction and moves with different velocities.They reaches their destination in 2 h and 1 h after crossing each other.What is the ratio of velocities of the train? If we assume that the distance travelled after they cross each other is the same, then we can set up a ratio.  We know that

`v=d/t` for both trains

and that can be rearranged to

d = v*t

If the distance is the same for both trains

d(A) = d(B)

then the following must also be true

v(A)*t(A) = v(B)*t(B)

Where v and t are the velocity and time of each train (designated by A or B).

We can then rearrange that to find

`(v(A))/(v(B)) = (t(B))/(t(A))`

Since we know that the time for train A is hour and for train B is 2 hours (assuming that because of the way they are written in the problem), then we know that

`(v(A))/(v(B))=2/1`

So Train A is travelling twice as fast as Train B.

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