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 10 of 11.
Nikky said:
7 years ago
Good explanation. Thanks @Amit.
Anagha said:
9 years ago
(4-2) * (5/18) * 9 * 10 = 50.
Jaga said:
7 years ago
Please explain @Nitesh Mittal.
Sidd said:
3 years ago
How? please anyone explain me.
(3)
Ayesha said:
9 years ago
Excellent shortcut @Anagha.
Swapnil said:
8 years ago
Awesome, thank you @Mancy.
Rajesh nande said:
8 years ago
Best solution @Idprasad.
GURU CHARAN MUNDA said:
3 years ago
Good, Thanks @Anushree.
(1)
Charan said:
7 years ago
Well said. Thanks all.
Muttu said:
6 years ago
@Amith is well solved.
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