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:
282 comments Page 1 of 29.
Hemant said:
2 weeks ago
@All.
First, identify the distance:
> Crossing a man/pole/tree?
Distance = Length of the train.
> Crossing a platform/bridge/tunnel?
Distance = Length of train + Length of platform.
> Crossing another train?
Distance = Length of Train A + Length of Train B.
First, identify the distance:
> Crossing a man/pole/tree?
Distance = Length of the train.
> Crossing a platform/bridge/tunnel?
Distance = Length of train + Length of platform.
> Crossing another train?
Distance = Length of Train A + Length of Train B.
(1)
Rajeshwari said:
1 month ago
Given:
Step1: Convert speed (km/hr)to(m/s) : (54*5/18)=15
Step2: Find the length of the train: speed*time required by the man standing on platform = 15 * 20 = 300 m
Step3: To find the length of the platform:
length of platform = x.
= (x + length of the train) /time required by the train to pass the station platform
15 = x + 300/36,
x + 300 = (15)(36),
x + 300 = 540,
x = 540 - 300,
x = 240m.
Step1: Convert speed (km/hr)to(m/s) : (54*5/18)=15
Step2: Find the length of the train: speed*time required by the man standing on platform = 15 * 20 = 300 m
Step3: To find the length of the platform:
length of platform = x.
= (x + length of the train) /time required by the train to pass the station platform
15 = x + 300/36,
x + 300 = (15)(36),
x + 300 = 540,
x = 540 - 300,
x = 240m.
(1)
Prathamesh Devrukhakar said:
5 months ago
@Sai.
1 km/hr = 5/18 m/s.
1 km/hr = 5/18 m/s.
(5)
Vamsi said:
8 months ago
54×5/18x(36 sec-20 sec).
= 15 × 16 = 240.
= 15 × 16 = 240.
(59)
Kiruthika said:
8 months ago
To find the length of the train why we use a 20-second time instead of 36 seconds? Anyone please explain to me.
(22)
Mahesh said:
9 months ago
Given,
Whole time spent on the platform as and assume it as t1 = 36 sec.
A man standing on the platform assumes it as t2 =20 sec.
We need the length of the platform.
Time (t1-t2) = 36 - 20 = 16sec.
Speed = 54 km/hr.
Convert km/hr to m/s.
1 km/hr = 1 * 5/18 m/s.
54 *5/18 = 3 * 5 = 15.
Length or distance of platform =speed * time.
=15 * 16 = 240m.
Whole time spent on the platform as and assume it as t1 = 36 sec.
A man standing on the platform assumes it as t2 =20 sec.
We need the length of the platform.
Time (t1-t2) = 36 - 20 = 16sec.
Speed = 54 km/hr.
Convert km/hr to m/s.
1 km/hr = 1 * 5/18 m/s.
54 *5/18 = 3 * 5 = 15.
Length or distance of platform =speed * time.
=15 * 16 = 240m.
(34)
Vishnu Kawale said:
10 months ago
Here, the length of the train is very small compared to real life.
(5)
ESNALA SIDDA said:
10 months ago
1) First calculate the train distance.
D = S×T.
S = 54×5/18,
S = 15m/s,
D = 15×20 = 300m.
2) Calculate the platform + train distance.
D = 36×15
= 540m
Platform distance
540 - 300 = 240m.
D = S×T.
S = 54×5/18,
S = 15m/s,
D = 15×20 = 300m.
2) Calculate the platform + train distance.
D = 36×15
= 540m
Platform distance
540 - 300 = 240m.
(39)
Uttam Roy said:
10 months ago
The speed of train = 54 x 5/18m/s,
= 15m/s.
Length of train = 15 x 20 = 300 meters ∴( distance = speed x time),
Total length = 15 x 30 = 540 (length of train x platform time taken to reach out),
The final answer is 540 - 300 meters.
= 240 meters.
= 15m/s.
Length of train = 15 x 20 = 300 meters ∴( distance = speed x time),
Total length = 15 x 30 = 540 (length of train x platform time taken to reach out),
The final answer is 540 - 300 meters.
= 240 meters.
(8)
T S SOUNDHAR said:
1 year 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.
(53)
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