Aptitude - Problems on Trains - Discussion

Consider the slower train as a man.

We can't find the slower train length as it will never pass the faster train.

So in order two find slower train length we need how much time the faster train take to pass the slower train not the man.

Relative means that slower is still.

Can anyone please explain how to calculate the length of slower train?

The thing is that when we find the relative speed, it means how their respective speeds change their positions and how their distance is varying, so with the help of the relative speed and the 5 second time which is the crossing time, for the tenure of 5 seconds we can find the length of the fastest train.

250/9 ==>we get.

Quotient = 27, Remainder = 7.
Then it will be in form quotient (remainder/divisor).

ie, 27 7/9.

How to convert 250/9 to mixed fraction? Please explain.

@Rohit Saluja.

When you consider relative velocity there is no need of knowing where the man is sitting and once you find out relative velocity the method of solving the problem is same as solving the problem of 'train passing a signal post or pole' so what they have given as solution is absolutely fine.

I also agree with you @Haritha.

It is not given that, where the man is sitting.

The Slower train is 500/9.

Hi, well in this question. We need the location where the man is sitting the slower train. So that we can find the distance which the faster train has to travel to cross the man sitting in slower train.

The solution to this assumes that the man is sitting at the end of the train. So in this case, length of slower train does not matter.

But assume if the man is sitting in middle of slower train, then faster train has to travel, it's own length plus half the length of slower train.