Answer
2.35 m/s
Work Step by Step
Let's take,
The velocity of the raindrops relative to the train = $V_{RT}$
The velocity of the raindrops relative to the ground = $V_{RG}$
The velocity of the ground relative to the train = $V_{GT}$
So, we can write.
$V_{RT}=V_{RG}+V_{GT}$
The velocity vector diagram shown in the image. Then, by using trigonometry.
$tan25^{\circ}=\frac{V_{GT}}{V_{RG}}=>V_{GT}=V_{RG}tan25^{\circ}=5\space m/s\times0.47=2.35\space m/s$
Speed of the train = 2.35 m/s
