Aptitude - Problems on Trains - Discussion
Discussion Forum : Problems on Trains - General Questions (Q.No. 25)
25.
A train 108 m long moving at a speed of 50 km/hr crosses a train 112 m long coming from opposite direction in 6 seconds. The speed of the second train is:
Answer: Option
Explanation:
Let the speed of the second train be x km/hr.
| Relative speed | = (x + 50) km/hr | |||||||
|
||||||||
|
![]](/_files/images/aptitude/1-sym-cbracket-h1.gif)
Distance covered = (108 + 112) = 220 m.
 |
220 | = 6 | ||
|
250 + 5x = 660
x = 82 km/hr.
Discussion:
77 comments Page 1 of 8.
Rajgowtham said:
1 decade ago
How the final answer comes in km per hour? First we are converting into metre per second so we need to convert it into km per hour.
Sundar said:
1 decade ago
Hi Raj,
Please note that
At the first step we are taking the speed of the second train be x KM/HR.
At final step we are finding the value of 'x'.
So, the answer is 'x' km/hr.
Thats why the answer is in km/hr.
Please note that
At the first step we are taking the speed of the second train be x KM/HR.
At final step we are finding the value of 'x'.
So, the answer is 'x' km/hr.
Thats why the answer is in km/hr.
(1)
Vishal Kumar said:
1 decade ago
But Raj, When we calculate the speed of second Train, then we also convert the time in hour. But in the above question time write it as it is, without any conversion of time.
If we want result in Km/hr then we also need to change the time in hour because both the trains takes 6 seconds to cross each other.
If we want result in Km/hr then we also need to change the time in hour because both the trains takes 6 seconds to cross each other.
Srinivas8126 said:
1 decade ago
Hi Sundar.
What you said is right we have taken x in terms on km/hr, considering above explanation while converting relative speed we use (x + 50) km/hr both speeds converted into meters/seconds in next step. So final answer will be in m/s how it will be in km/hr?.
What you said is right we have taken x in terms on km/hr, considering above explanation while converting relative speed we use (x + 50) km/hr both speeds converted into meters/seconds in next step. So final answer will be in m/s how it will be in km/hr?.
Priyavel said:
1 decade ago
Hi.
I can't get it clearly. Please anyone explain it.
I can't get it clearly. Please anyone explain it.
Ramesh said:
1 decade ago
(220)m
----------------- =6 sec.
((250+5x)/18)m/s
here,m and s are cancelled so x km/hr.
----------------- =6 sec.
((250+5x)/18)m/s
here,m and s are cancelled so x km/hr.
Deepa Singh said:
1 decade ago
Please solve this part clearly 220/(5x+250)/18=6
Gargi Banerjee said:
1 decade ago
Please give an appropriate answer with perticular reason, this is not clear to me.
Ambika said:
1 decade ago
Length of the trains=108+112=220m=(220/1000)=(11/50)km
Let the speed of second train be xkm/hr
therefore,relative speed=(50+x)km/hr(since it is opposite direction the speeds should be added)
time=6sec=(6/3600)=(1/600)hr
then solve using the formula time=(distance/speed)
i.e (11/50)/(50+x)=(1/600)
after solving x will be 82km/hr
Let the speed of second train be xkm/hr
therefore,relative speed=(50+x)km/hr(since it is opposite direction the speeds should be added)
time=6sec=(6/3600)=(1/600)hr
then solve using the formula time=(distance/speed)
i.e (11/50)/(50+x)=(1/600)
after solving x will be 82km/hr
Muthulakshmi said:
1 decade ago
Hai Mr.Ramesh
You are Correct.Thanks for explaining the problem clearly
You are Correct.Thanks for explaining the problem clearly
Post your comments here:
Quick links
Quantitative Aptitude
Verbal (English)
Reasoning
Programming
Interview
Placement Papers