A train overtakes two persons who are walking in the same direction in which the train is going, at the rate of 2 kmph and 4 kmph and passes them completely in 9 and 10 second respectively. The length of the train is. (1) 45 metres (2) 40 metres (3) 54 metres (4) 50 metres

 The correct answer is (4) 50 metres


Let the length of train be x km

Let the speed of the train be y km/hr

2 kmph = (2 x 5/18) m/sec = 5/9 m/sec.

4 kmph = (4 x 5/18) m/sec = 10/9 m/sec.

According to the given condition

 x/(y-2) = 9/(60*60)
x/(y-4) = 10/(60*60)

On combining both the equations we get
9y – 3600x = 18
and 10y – 3600x = 40
y-400x = 2

and y – 360x = 4
40x = 2 

x = (2/40 *1000)m

= 50 metres

Getting Info...
Cookie Consent
We serve cookies on this site to analyze traffic, remember your preferences, and optimize your experience.
It seems there is something wrong with your internet connection. Please connect to the internet and start browsing again.
AdBlock Detected!
We have detected that you are using adblocking plugin in your browser.
The revenue we earn by the advertisements is used to manage this website, we request you to whitelist our website in your adblocking plugin.
Site is Blocked
Sorry! This site is not available in your country.