Aptitude - Problems on Trains - Discussion
Discussion Forum : Problems on Trains - General Questions (Q.No. 6)
6.
A train 240 m long passes a pole in 24 seconds. How long will it take to pass a platform 650 m long?
Answer: Option
Explanation:
| Speed = |  |
240 |  m/sec = 10 m/sec. |
| 24 |
 Required time = |
|
240 + 650 | sec = 89 sec. |
| 10 |
Discussion:
204 comments Page 8 of 21.
The Guide said:
1 decade ago
For problems on trains for most of the problems we use one formulae
time=(l1+l2)/s1+s2
for eg in the above problem
given length of train 240m and time 24 sec then speed=10m/sec
given length of platform 650
their is no speed s2 because platform is a stationary object
so substitue all the values in above formulae
we get time t=(240+650)/10= 89sec
time=(l1+l2)/s1+s2
for eg in the above problem
given length of train 240m and time 24 sec then speed=10m/sec
given length of platform 650
their is no speed s2 because platform is a stationary object
so substitue all the values in above formulae
we get time t=(240+650)/10= 89sec
Rahul said:
1 decade ago
If we are asked only the time taken to cover 650 m long platform, then the rigth answer is 65.
If we are asked to find the total time to cover the whole distance (240+650) , then the rigth answer is 89.
If we are asked to find the total time to cover the whole distance (240+650) , then the rigth answer is 89.
Sonal said:
1 decade ago
Can you tell me, why did we get 240 two times?
(Firstly 240/24, then after 240+650/10) So please explain me.
(Firstly 240/24, then after 240+650/10) So please explain me.
Shro said:
1 decade ago
Thanku Rahul for clearing Confusion :)
Shro said:
1 decade ago
Thanks Kirubanidhi for the right explanation :).
Vino said:
1 decade ago
@sonal,
First we find the TIME of the train. So we get 240/24=10m/1s.
Next we find the total DISTANCE of the train. So we get 240+650=890.
Finally.
Speed=distance/time.
=890/10.
=89sec.
First we find the TIME of the train. So we get 240/24=10m/1s.
Next we find the total DISTANCE of the train. So we get 240+650=890.
Finally.
Speed=distance/time.
=890/10.
=89sec.
Varun Kumar Saraswat said:
1 decade ago
Total distance= Total length of train + Length of platform
Satish said:
1 decade ago
Train of length 240 mts.....
It covers 240 mts in 24 sec...
During crossing a bridge it has to cover 650 mts additional to 240....
So 240mts in 24 sec
Then (240+650) in x sec
i.e x=24*890/240===>89
It covers 240 mts in 24 sec...
During crossing a bridge it has to cover 650 mts additional to 240....
So 240mts in 24 sec
Then (240+650) in x sec
i.e x=24*890/240===>89
Ravi said:
1 decade ago
I am done my way.
If its takes 24s to cross 240m,
So how much it'l take to cross 650m long platform. 240+650=890.
You just put one equation like.
240m=24s.
890m=?, then cross multiplication.
890*24/240=89.
If its takes 24s to cross 240m,
So how much it'l take to cross 650m long platform. 240+650=890.
You just put one equation like.
240m=24s.
890m=?, then cross multiplication.
890*24/240=89.
Rasim said:
1 decade ago
We can calculate the train speed by considering pole as a reference point
train length=240m
time taken by a train to pass a pole =24sec
s=d/t
s=(240/24)
s=10m/sec
platform length=650m
we know that
total distance=speed*time
650+240=10*t
890=10*t
t=89sec
train length=240m
time taken by a train to pass a pole =24sec
s=d/t
s=(240/24)
s=10m/sec
platform length=650m
we know that
total distance=speed*time
650+240=10*t
890=10*t
t=89sec
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