Aptitude - Problems on Trains - Discussion
Discussion Forum : Problems on Trains - General Questions (Q.No. 2)
2.
A train 125 m long passes a man, running at 5 km/hr in the same direction in which the train is going, in 10 seconds. The speed of the train is:
Answer: Option
Explanation:
| Speed of the train relative to man = |  |
125 |  m/sec |
| 10 |
| = | |
25 | m/sec. |
| 2 |
| = | |
25 | x | 18 | km/hr |
| 2 | 5 |
= 45 km/hr.
Let the speed of the train be x km/hr. Then, relative speed = (x - 5) km/hr.
x - 5 = 45 
x = 50 km/hr.
Discussion:
493 comments Page 25 of 50.
Srinivas Rao said:
1 decade ago
If both things are in the same direction, then we have to do subtraction right but why we have to do it.
Rishi said:
1 decade ago
Answer must be 55, Because train has to cover 125m+distance covered by man in 10 sec which is 5*10/3600.
Nitesh Nandwana said:
2 decades ago
Hai Rahul, well explanation about relative speed and same and opposite directions. Good job keep it up.
Shobi said:
1 decade ago
Hi friends,
I ave confuesion in relative speed. Can I have some more explanation about relative speed?
I ave confuesion in relative speed. Can I have some more explanation about relative speed?
GwenBiz said:
1 decade ago
@Jothi,
x-5 = 45.
We add 5 to both sides so that we stay with x.
x-5+5 = 45+5.
Therefore,
So x = 50.
x-5 = 45.
We add 5 to both sides so that we stay with x.
x-5+5 = 45+5.
Therefore,
So x = 50.
Sai said:
1 decade ago
This concept is relative to distance not to time so you cannot take a relation like you have mentioned.
Stark said:
1 decade ago
Correct your equation to 125/v1-(10*5)/(5*18) = 10 you will get.
v1 = 13.88 m/s.
==> v1 = 50 kmph.
v1 = 13.88 m/s.
==> v1 = 50 kmph.
Sonali said:
7 years ago
If only one of the speed is given then how will we consider that which one is to be subtracted or not?
Kannips said:
2 decades ago
speed=distance/time.so speed=125/10.....25/2*18/5=45... the question is same direction=x-5=45 x=50
Anish said:
1 decade ago
Hi Manishkumar,Vijaykumarkuppani,Umesh
U hav cleard the points exactly how itz done.
Thanks a lot...
U hav cleard the points exactly how itz done.
Thanks a lot...
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