lum28 wrote:

hello everyone,

Please consider this problem:

There is a tunnel having point 'A' and point 'B' as its front and rear ends respectively. A train is approaching point 'A' of tunnel and a cat is lying in the tunnel at point 'C' which is at a distance of 3/8th of tunnel's length from point 'A'. If the cat runs either ways (towards front or rear end of the tunnel), it meets the train and hence the cat is killed by the train. What is the ratio of their speeds?

[Answer: 4:1]

How to solve this problem? Please tell.

P.S. I saw this problem on a YouTube channel. If anyone wants, I can share the link.

The exact question is -

A train approaches a tunnel AB. Inside the tunnel is a cat located at a point that is 3/8 of the distance AB measured from the entrance A. When the train whistles the cat runs. If the cat moves to the entrance of the tunnel A, the train catches the cat exactly at the entrance. If the cat moves to the exit B, the train catches the cat exactly at the exist. The speed of the train is greater than the speed of the cat by what order?

A. 3 : 1

B. 4 : 1

C. 5 : 1

D. None of these

And the OE is -

Let the train be at a distance y from A. Let the length of the tunnel AB be 8x. Therefore, the cat is at 3x from A.

Now both the conditions given in the questions assume same time scenario. Therefore, the ratio of the speeds of

the cat and the train will be equal to the ratio of the distances traveled by them.

Required ratio,

= > y/3x = (y +8x)/5x

=> y = 12.

Therefore, ratio of the speed = y/3x = 12x/3x = 4 : 1.

Source :

https://www.examveda.com/a-train-approa ... n-the-874/
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Thanks and Regards

Abhishek....

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