Question

A moving train crosses a man standing on a platform and the platform 300m long in 10sec and 25 sec respectvely.what will be the time taken by the train to cross a platform 200m long.

Answer 1

Answer:

20 seconds.

Step-by-step explanation:

Train crosses the platform whose length is 300 metres in25−10=15 seconds, here train's length is not added.

So speed of the train =300/15 = 20 m/sec  

length of the train = 10×20 = 200 metres

Time taken by the train to cross a platform 200 metre long  

=length of train + platform / speed

=(200+200)20=400/20

Time taken by train = 20 seconds.

Answer 2

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Solution :-

Let speed train is x .

Length of train = x × 10 = 10x m-----------1

=> Speed of train = (10x +300)/ 25

=> x = (10x +300)/ 25

=> 25x = 10x +300

=> 15x = 300

=> x = 20 m/s

Length of train =10x = 200m

Time taken by train to cross a platform = (200+200) /20 = 20s

correct answer is 20 second .
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