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 7 of 11.
Yogesh said:
1 decade ago
Multiply The eq1 by 10, IT will become 90y-10x=50. Now subtract eq1 from from 2.
Anushree Kulkarni said:
3 years ago
Distance = length of the train.
D = S * T.
D = (4-2)*5/18*90,
Therefore D = 50.
D = S * T.
D = (4-2)*5/18*90,
Therefore D = 50.
(41)
Rakshikasaravanan said:
5 years ago
Speed = 2 - 4 = 2kmps.
S = 2 * 5/18 = 5/9m/s.
L = s * t
L= 5/9 * 9 * 10
L= 50.
S = 2 * 5/18 = 5/9m/s.
L = s * t
L= 5/9 * 9 * 10
L= 50.
(3)
Arvind said:
1 decade ago
@Yogesh,
By doing that we are not getting 50.
Got x = 50/8.
Please explain?
By doing that we are not getting 50.
Got x = 50/8.
Please explain?
Anu malik said:
9 years ago
Can't understand, please, tell me how to explain it in short cut method?
Jaimin said:
8 years ago
Can anyone explain the relation of time in detail: (t1*t2)/(t1-t2).
Vinay said:
1 decade ago
Kapil finally it is 55/9 not 55/11 ok, you had solved really great.
VamC said:
7 years ago
Why we should consider y-5/9 and y-10/9 in Denominators (Speed) ?
Jitendra raghuvanshi said:
1 decade ago
What is find out by 5/9 and 2/9.
I mean is it speed of train ?
I mean is it speed of train ?
Mamatha said:
1 decade ago
Please can any one of you tell me the problem in easy method ?
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