Aptitude - Problems on Trains - Discussion
Discussion Forum : Problems on Trains - General Questions (Q.No. 3)
3.
The length of the bridge, which a train 130 metres long and travelling at 45 km/hr can cross in 30 seconds, is:
Answer: Option
Explanation:
| Speed = |  |
45 x | 5 |  m/sec |
= | |
25 | m/sec. |
| 18 | 2 |
Time = 30 sec.
Let the length of bridge be x metres.
| Then, | 130 + x | = | 25 |
| 30 | 2 |
2(130 + x) = 750
x = 245 m.
Video Explanation: https://youtu.be/M_d8WufJWKc
Discussion:
245 comments Page 24 of 25.
Coolburn said:
1 decade ago
Hi, I had my own solustion on that
45 km/hr
1km = 1000m
1hr = 3600 sec
45 km/hr convert to metter
=45000 m
=3600 sec.
45000/3600
=12.5
Since 30 sec can cross the bridge
=12.5*30
=375-130
=245m
45 km/hr
1km = 1000m
1hr = 3600 sec
45 km/hr convert to metter
=45000 m
=3600 sec.
45000/3600
=12.5
Since 30 sec can cross the bridge
=12.5*30
=375-130
=245m
(1)
Boopathi said:
1 decade ago
Hey how is it possible to come.
2 (130 + x) = 750.
X = 245 m.
Please advice me.
2 (130 + x) = 750.
X = 245 m.
Please advice me.
Mahes said:
1 decade ago
I have solved this problem in a different way, is this right way to solve?
Speed = 25/2 m/sec
Length of the bridge be x m.
Total distance = Speed * Time
x + 130 = 30 * 25/2
x + 130 = 375
x = 245 m
Is the above method to solve this problem right?
Please explain.
Speed = 25/2 m/sec
Length of the bridge be x m.
Total distance = Speed * Time
x + 130 = 30 * 25/2
x + 130 = 375
x = 245 m
Is the above method to solve this problem right?
Please explain.
Atul said:
1 decade ago
Plz give me trick to solve to this. Bcz compny gives 1 minute /question and question is so lengthy, then how can I mange my time.
Hari said:
2 decades ago
Super.
Rahul said:
2 decades ago
@deepika @nattu
speed= train length + bridge length
----------------------------
time taken to cross
we know train length, speed and time taken. find out bridge length.
speed= train length + bridge length
----------------------------
time taken to cross
we know train length, speed and time taken. find out bridge length.
Nattu said:
2 decades ago
But crossing chould mean the whole train should be off the bridge right? So why should we subtract the length of the train?
Naveen kumar said:
2 decades ago
Hi jose, by cross mulyiplication method it will come as
2(130 + x) = 25*30
then 2(130 + x) = 750
then (130+x)=750/2
then (130+x)=375
then x=375-130
then finally ength of the bridge is 245m.
2(130 + x) = 25*30
then 2(130 + x) = 750
then (130+x)=750/2
then (130+x)=375
then x=375-130
then finally ength of the bridge is 245m.
Jose said:
2 decades ago
Hey how is possible to come ?
2(130 + x) = 750
x = 245 m.
please advice me
2(130 + x) = 750
x = 245 m.
please advice me
Nusrat Fathima said:
2 decades ago
Thanks karthik
Sai the method mentioned by u is also a right method to solve the above problem..... Good thinking.
Sai the method mentioned by u is also a right method to solve the above problem..... Good thinking.
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