Aptitude - Problems on Trains - Discussion
Discussion Forum : Problems on Trains - General Questions (Q.No. 16)
16.
A train travelling at a speed of 75 mph enters a tunnel 3
miles long. The train is 
mile long. How long does it take for the train to pass through the tunnel from the moment the front enters to the moment the rear emerges?
miles long. The train is mile long. How long does it take for the train to pass through the tunnel from the moment the front enters to the moment the rear emerges?Answer: Option
Explanation:
| Total distance covered |
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 Time taken |
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| = 3 min. |
Discussion:
129 comments Page 1 of 13.
Shubham said:
4 years ago
Ans must be 3.2 min.
We have to take the length of train twice.
7/2 + 1/4 + 1/4 = 4 miles.
Then,
Time = 4/75.
=0.05333 hr.
In seconds 0.05333*60= 3.198 which is 3.2 min.
We have to take the length of train twice.
7/2 + 1/4 + 1/4 = 4 miles.
Then,
Time = 4/75.
=0.05333 hr.
In seconds 0.05333*60= 3.198 which is 3.2 min.
(23)
Kolli Hemanth said:
2 years ago
@All.
Here mph means meters per hour but the distance is given in miles. So, miles must be converted into meters. 1 mile=1609 meters.
Here mph means meters per hour but the distance is given in miles. So, miles must be converted into meters. 1 mile=1609 meters.
(15)
Harish said:
2 years ago
Train distance is in miles and speed is in meters without conversion of miles into meters how can we compare both?
Anyone, please clarify this.
Anyone, please clarify this.
(14)
Sagnik Bhunia said:
1 year ago
Train length must be multiplied by 2 and added tunnel length to get the total distance as the problem says train starts from entering the tunnel from front to exiting the tunnel till its end.
Shouldn't it be the correct interpretation? Anyone, Please clarify.
Shouldn't it be the correct interpretation? Anyone, Please clarify.
(12)
Shyam said:
3 years ago
The speed of the train = 75mph.
=75 * 1/60.
Train speed = 5/4seconds.
The total distance is (7/2 + 1/4),
= 15/4mile.
Formula of time = distance /speed.
= 15/4/5/4.
= 15/4 * 4/5.
= 3seconds.
=75 * 1/60.
Train speed = 5/4seconds.
The total distance is (7/2 + 1/4),
= 15/4mile.
Formula of time = distance /speed.
= 15/4/5/4.
= 15/4 * 4/5.
= 3seconds.
(8)
Kishan Maurya said:
4 years ago
Length of train will be 2 times of 1/4.
And correct ansr is 3.2min.
And correct ansr is 3.2min.
(6)
Atikraja Khochikar said:
2 years ago
How 7/2 came? anyone explain me.
(6)
Asli_hai said:
4 years ago
The question says front contact and back part emerges out that means the length of tunnel + 2 times length of the train.
So the answer will be 3.2.
So the answer will be 3.2.
(5)
Arbaj Tamboli said:
4 years ago
75 mph means 75 miles per hour.
(5)
Jahnavi said:
4 years ago
1meter = 0.0006 miles.
So, the conversion of meters to miles is not required.
You can directly calculate the time without changing units.
Note: The length of the train need not be taken twice. This is similar to the bridge problem (train crossing the bridge).
So, the conversion of meters to miles is not required.
You can directly calculate the time without changing units.
Note: The length of the train need not be taken twice. This is similar to the bridge problem (train crossing the bridge).
(5)
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