Answer:
The total distance the bird travels is d.
Explanation:
Each train travels at the speed s. They will meet at the center, a distance d/2 (which is where the bird might be crushed). Each train travels the same distance d/2 in a time t which is also equal for both. This is also the time the bird spends travelling between them.
For any of the train, the time t is the distance divided by the speed.
[tex]t = \dfrac{d/2}{s} = \dfrac{d}{2s}[/tex]
The bird travels at the speed of 2s. Its distance is given by the product of its speed and the time taken.
[tex]d_\text{Bird} = \dfrac{d}{2s}\times 2s = d[/tex]
