Aptitude - Problems on Trains - Discussion
Discussion Forum : Problems on Trains - General Questions (Q.No. 27)
27.
A train overtakes two persons who are walking in the same direction in which the train is going, at the rate of 2 kmph and 4 kmph and passes them completely in 9 and 10 seconds respectively. The length of the train is:
Answer: Option
Explanation:
| 2 kmph = |  |
2 x | 5 |  |
m/sec = | 5 | m/sec. |
| 18 | 9 |
| 4 kmph = | |
4 x | 5 | |
m/sec = | 10 | m/sec. |
| 18 | 9 |
Let the length of the train be x metres and its speed by y m/sec.
| Then, |  |
x |  |
= 9 and | |
x | |
= 10. |
|
|
9y - 5 = x and 10(9y - 10) = 9x
9y - x = 5 and 90y - 9x = 100.
On solving, we get: x = 50.
Length of the train is 50 m.
Discussion:
106 comments Page 8 of 11.
Sasikumar said:
2 decades ago
Why 5/9 is subtracted with y? Please any one tell the answer.
Raksha said:
5 years ago
I did not get it properly. Could someone explain me briefly?
Priyanshu said:
4 years ago
I didn't understand the solution, anyone explain it please.
(2)
Raja said:
9 years ago
@K. Anitha.
I didn't get your last step. Please explain.
I didn't get your last step. Please explain.
Akhilesh Mehta said:
9 years ago
@Karuna.
It is for converting the speed Km/h to m/sec.
It is for converting the speed Km/h to m/sec.
Shubham said:
9 years ago
How can we calculate the speed of the train in this?
Suraj said:
7 years ago
Please tell me that, where did the 5/18 come from?
Chandini said:
3 years ago
Why we multiply 9 and 10 here? can anyone explain?
(22)
Erram saicharan said:
7 years ago
Why y is considered as m/s?
Please explain that.
Please explain that.
Karuna said:
9 years ago
What is that 5/18 and why should we take that?
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