Aptitude - Problems on Trains - Discussion
Discussion Forum : Problems on Trains - General Questions (Q.No. 10)
10.
A jogger running at 9 kmph alongside a railway track in 240 metres ahead of the engine of a 120 metres long train running at 45 kmph in the same direction. In how much time will the train pass the jogger?
Answer: Option
Explanation:
Speed of train relative to jogger = (45 - 9) km/hr = 36 km/hr.
| = |  |
36 x | 5 |  m/sec |
| 18 |
= 10 m/sec.
Distance to be covered = (240 + 120) m = 360 m.
 Time taken = |
|
360 | sec |
= 36 sec. |
| 10 |
Discussion:
106 comments Page 5 of 11.
Raj vora said:
9 years ago
Can you please explain why we have to add 240 + 120?
Shubham said:
9 years ago
as (a+b/u-v).
(45-9) * 5/18 = 10m/s.
(120 + 240/10) = 36s.
(45-9) * 5/18 = 10m/s.
(120 + 240/10) = 36s.
Shubh said:
9 years ago
What will be the shortcut method if trains are moving in opposite directions?
Raaj said:
9 years ago
If the direction of both things is in the same direction then the relative speed will be subtracted but in the case of opposite direction, relative speed will be added.
Priya said:
9 years ago
What is the unit digit of 991^45? Can anyone tell me?
Sandeep said:
9 years ago
Can anyone explain by using formula a + b / u - v?
Ayush Chawla said:
9 years ago
Could the answer be wrong? Because, according to answer jogger is idle, as the distance covered by the jogger is not considered in the total answer? According to me, 48sec should be the right answer.
Could anyone give it a thought? That total distance should be 240 + 120 + T * 9 * (5/18) , supposing x is a distance moved by a jogger. Therefore x = T * (9 * 5/18).
Then the answer is 48, which is not mentioned in options.
Could anyone give it a thought? That total distance should be 240 + 120 + T * 9 * (5/18) , supposing x is a distance moved by a jogger. Therefore x = T * (9 * 5/18).
Then the answer is 48, which is not mentioned in options.
Naveen said:
9 years ago
@Sailesh, What you said is correct.
Niveditha said:
9 years ago
It's better to use shortcut method.
t = a + b /u - v.
t = a + b /u - v.
Sailesh said:
9 years ago
They asked how much time the train pass jogger. Should the entire train pass the jogger (then distance=240 + 120) or should the engine only just pass the jogger (then distance =240).
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