Aptitude - Problems on Trains - Discussion
Discussion Forum : Problems on Trains - General Questions (Q.No. 5)
5.
A train passes a station platform in 36 seconds and a man standing on the platform in 20 seconds. If the speed of the train is 54 km/hr, what is the length of the platform?
Answer: Option
Explanation:
| Speed = |  |
54 x | 5 |  m/sec = 15 m/sec. |
| 18 |
Length of the train = (15 x 20)m = 300 m.
Let the length of the platform be x metres.
| Then, | x + 300 | = 15 |
| 36 |
x + 300 = 540
x = 240 m.
Discussion:
276 comments Page 7 of 28.
Adesh Katiya said:
2 years ago
t1 =36s
t2 = 20s
s= 54km/hr
l=??
d1 = s*t
d1 = 54*(5/18) * 36
d1 = 15m/s * 36
d1 = 540m.
d2 = 15*20.
d2 = 300m.3
300m is the distance up to the man standing and the length of the total platform would be greater than this. so,
300 + x = 540m.
x = 240m.
t2 = 20s
s= 54km/hr
l=??
d1 = s*t
d1 = 54*(5/18) * 36
d1 = 15m/s * 36
d1 = 540m.
d2 = 15*20.
d2 = 300m.3
300m is the distance up to the man standing and the length of the total platform would be greater than this. so,
300 + x = 540m.
x = 240m.
(10)
Gopu said:
1 decade ago
Simple method;.
Convert train speed into m/sec=54*5/18.
=15m/s.
Subtract train time which it had taken to cross a man from the time taken by train to cross the platform i.e,
= (36-20).
=16.
Now apply formula of distance i.e. speed*time.
=15*16.
=240. ) ).
Convert train speed into m/sec=54*5/18.
=15m/s.
Subtract train time which it had taken to cross a man from the time taken by train to cross the platform i.e,
= (36-20).
=16.
Now apply formula of distance i.e. speed*time.
=15*16.
=240. ) ).
Manna said:
8 years ago
@ALL.
Logically, the length of the train should be more or less equal to the length of the platform else it will be troublesome for the passengers to cover that distance. And the solution assumes that the man is standing at the beginning of the platform.
Logically, the length of the train should be more or less equal to the length of the platform else it will be troublesome for the passengers to cover that distance. And the solution assumes that the man is standing at the beginning of the platform.
Satheesh said:
1 decade ago
Hi Guys
1 Km=1000 Meters
1 hr=3600 seconds
If the speed of the train is 54 km/hr
54*1000= 54000
54000/3600=15
A train passes a station platform in 36 seconds
15*36=540
a man standing on the platform in 20 seconds
15*20=300
540-300=240
Ans:240 Simple
1 Km=1000 Meters
1 hr=3600 seconds
If the speed of the train is 54 km/hr
54*1000= 54000
54000/3600=15
A train passes a station platform in 36 seconds
15*36=540
a man standing on the platform in 20 seconds
15*20=300
540-300=240
Ans:240 Simple
Karthik said:
1 decade ago
Shortcut:
Minus the both time of the train to cross the platform as well as man (reference point).
T = 36 sec, t = 20 sec.
T - t = 16 sec.
With the normal formula Length = Speed * Time
(i.e) 15 m/s * 16 sec = 240 metres.
Minus the both time of the train to cross the platform as well as man (reference point).
T = 36 sec, t = 20 sec.
T - t = 16 sec.
With the normal formula Length = Speed * Time
(i.e) 15 m/s * 16 sec = 240 metres.
T S SOUNDHAR said:
4 months ago
Train cross the platform is 36sec.
A man standing (passenger for boards) is = 20 sec,
Total train running time on the platform is = 36 - 20 = 16sec.
So,
54km/hr = 54000/3600 = (540/36) = 15m/s,
platform length = 16 * 15 = 240m is the answer.
A man standing (passenger for boards) is = 20 sec,
Total train running time on the platform is = 36 - 20 = 16sec.
So,
54km/hr = 54000/3600 = (540/36) = 15m/s,
platform length = 16 * 15 = 240m is the answer.
(43)
Sahil said:
2 decades ago
Distance= speed*time
300=15*20
this is length of a train only and we have to find out length of a plateform so we add length of both train and plateform becoz in case of bridge or plateform we can add both the length.
then
x+300/36=15
=240m
300=15*20
this is length of a train only and we have to find out length of a plateform so we add length of both train and plateform becoz in case of bridge or plateform we can add both the length.
then
x+300/36=15
=240m
Rakesh said:
4 years ago
I have solved this problem in a different way, is this the right way to solve it?
Speed=15 m/sec.
Total length of train is 300m,
let length of the plateform be x m,
total distance = speed * time,
x + 300 = 15*36,
x + 300 = 540,
x = 240m.
Speed=15 m/sec.
Total length of train is 300m,
let length of the plateform be x m,
total distance = speed * time,
x + 300 = 15*36,
x + 300 = 540,
x = 240m.
(4)
Sikkanthar said:
1 decade ago
Nice answers. Here they are using the formula is,
(train length + plat form length) / time = speed.
They are calculating the length of the train by using the given data.
Then substitute all the known values and finally got the result.
(train length + plat form length) / time = speed.
They are calculating the length of the train by using the given data.
Then substitute all the known values and finally got the result.
Pawan said:
1 decade ago
It is longest but easy to undertand
len = speed*time
speed: 54*5/18=15
Now calculate the length of train,
len=15*20
=300
now calculate the length of platform
use same formula (x=platform length)
300+x=15*36
x=540-300
x=240
len = speed*time
speed: 54*5/18=15
Now calculate the length of train,
len=15*20
=300
now calculate the length of platform
use same formula (x=platform length)
300+x=15*36
x=540-300
x=240
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