Wind is blowing to east along two parallel railway tracks. Two trains moving with the same speed in opposite direction have the steam track of one double that of the other. The speed of each train is

Let V and u be the speed of train and wind respectively Also let train -1 is running due east and train-2 is running due west.For train-1 , length of steam track in a given time t ,l1 = vt - ut = (v-u) tand for train - 2 , l2 = vt + ut = (v+u)tsince l2 = 2l1 , we can write(v+u)t = 2 x (v - u) t ⇒V = 3u