Monday, October 31, 2005

Interesting puzzles - 6

Back to puzzles.

A man is walking through a long railway tunnel and is 1/3 rd through when he hears the sound of a train approaching from far. As it turns out, he would have narrowly escaped from the train by continuing forward or going backward without changing his current speed. What is his speed if the train is moving at 20kmph.

Try to solve this without using math equations and such. I think it was OP who clued me on these kind of problems in college :)

3 comments:

Vishal Grover said...

is it 20/3 km/hr?

Kalyan said...

Yup :)

Anonymous said...

Wow, it took me forever, but I got it right. And with worlds most complicated drawing/calculation.
How did you get something as simple as 20/3?
I calculated the time it would take for the train to be at the end, then at the beginning, which gave me the size of the tunnel, and then calculated his speed. Also coming to 6 2/3.