Aptitude - Problems on Trains - Discussion
Discussion Forum : Problems on Trains - General Questions (Q.No. 11)
11.
A 270 metres long train running at the speed of 120 kmph crosses another train running in opposite direction at the speed of 80 kmph in 9 seconds. What is the length of the other train?
Answer: Option
Explanation:
Relative speed = (120 + 80) km/hr
| = |  |
200 x | 5 |  m/sec |
| 18 |
| = | |
500 | m/sec. |
| 9 |
Let the length of the other train be x metres.
| Then, | x + 270 | = | 500 |
| 9 | 9 |
x + 270 = 500
x = 230.
Discussion:
66 comments Page 4 of 7.
Umar bodha said:
8 years ago
Trains running in opp directions.
Relative speed 120+80 =200.
By converting into m/s,
200*5÷18 =500/,
We know by formula
L=s*t.
Let x be the length of another train
Therefore
X+270=500÷9*9.
X=500-270= 230.
So, x=230m.
Relative speed 120+80 =200.
By converting into m/s,
200*5÷18 =500/,
We know by formula
L=s*t.
Let x be the length of another train
Therefore
X+270=500÷9*9.
X=500-270= 230.
So, x=230m.
Karn sharma said:
1 decade ago
Trains are move in opposite direction. But out of speed n distance one quantity is subtract but in the solution of this question both are added. Please explain I can't understand.
Nilkant said:
7 years ago
Please, tell me when to find relative speed?
Pramod said:
1 decade ago
Two trains are in opposite travelling in the opposite direction. So how can can add their length? It has to be be subtraction. If they are moving in the same direction then add only.
Sabira said:
1 decade ago
Speed = 120+80 = 200 km/hr.
200* (5/18) = 500/9m/sec.
Total length = 500/9*9.
= 500 m.
500 - 270 = 230 is the other train length.
200* (5/18) = 500/9m/sec.
Total length = 500/9*9.
= 500 m.
500 - 270 = 230 is the other train length.
Aswin said:
1 decade ago
Please let me know, where 100/3 comes from?
Amudha said:
1 decade ago
To find length of one train why we are calculating relative speed?
Amar said:
1 decade ago
kmph means kilometer per hour(Km/h).
Krishna said:
1 decade ago
The speed & time of the other so we can directly get the length of the other train.
Kadoliya jitendra said:
1 decade ago
What is kmph?
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