Question

A train clears a platform of 200 meters long in 15 seconds and passes a telegraph post in 10 seconds.The length of the train is?

Answer 1

train length=X
X/10=X+200/15
15x=10x+2000
5x=2000
x=400
train length = 400 meter

Answer 2

Answer:

The length of train is 400 meters.

Step-by-step explanation:

Let the length of train be x.

It is given that a train clears a platform of 200 meters long in 15 seconds.

Total distance covered by train is

$D=200+x$

The formula for speed is

$Speed=\frac{Distance}{Time}$

The speed of train is

$Speed=\frac{200+x}{15}$             .... (1)

It given that the train passes a telegraph post in 10 seconds.

The speed of train is

$Speed=\frac{x}{10}$             .... (2)

From (1) and (2), we get

$\frac{200+x}{15}=\frac{x}{10}$

$2000+10x=15x$

$2000=15x-10x$

$2000=5x$

$400=x$

Therefore the length of train is 400 meters.