Aptitude - Problems on Trains - Discussion
Discussion Forum : Problems on Trains - General Questions (Q.No. 8)
8.
A train 360 m long is running at a speed of 45 km/hr. In what time will it pass a bridge 140 m long?
Answer: Option
Explanation:
| Formula for converting from km/hr to m/s: X km/hr = |  |
X x | 5 |  |
m/s. |
| 18 |
| Therefore, Speed = | |
45 x | 5 | m/sec |
= | 25 | m/sec. |
| 18 | 2 |
Total distance to be covered = (360 + 140) m = 500 m.
| Formula for finding Time = | |
Distance | |
| Speed |
 Required time = |
|
500 x 2 | sec |
= 40 sec. |
| 25 |
Discussion:
78 comments Page 2 of 8.
Shubham Jain said:
6 years ago
How come 25/2?
(1)
Nibha said:
6 years ago
Why 140m is added?
(1)
Sai said:
7 years ago
450mts ----> 36sec.
500mts ---> 40sec.
500mts ---> 40sec.
(1)
Anush said:
7 years ago
Why we are adding the train length with bridge length?
(1)
Sujith kumar said:
10 years ago
Speed = 45km/hr = 45 * 1000/60 * 60 = 12.5m/ec.
Length = Speed * Time.
360 + 140 = 12.5 * time.
Time = 500/12.5 = 40sec.
Length = Speed * Time.
360 + 140 = 12.5 * time.
Time = 500/12.5 = 40sec.
(1)
Satish said:
1 decade ago
When a train is crossing a bridge means that train is crossing it's own length and the bridge length. If you see at the end of the compartment to be crossed the bridge, the length of the bridge is depending on the train length, if the train is shorter the the time taken to cross the bridge will be lesser and if the train is longer, the time taken to bridge will be larger to cross at the end of the compartment.
(1)
Sam said:
2 decades ago
Hi How x*5/18 came there can't understand
PANASA HARISH KUMAR said:
1 decade ago
Train long = 360m.
Speed 45*5/18 = 12.5m/sec.
Bridge long = 140m.
Time = ?
Speed = Distance/Time
12.5 = 360 + 140/time.
Time = 40sec.
Speed 45*5/18 = 12.5m/sec.
Bridge long = 140m.
Time = ?
Speed = Distance/Time
12.5 = 360 + 140/time.
Time = 40sec.
Virang soni said:
10 years ago
d = s * t = 45 * (5/18) = 12.5.
Total length = 360 + 140/12.5 = 40.
Total length = 360 + 140/12.5 = 40.
Anonymous said:
10 years ago
In this question, the length of the bridge is shorter than that of the train. Then why we go for adding the two lengths?
Post your comments here:
Quick links
Quantitative Aptitude
Verbal (English)
Reasoning
Programming
Interview
Placement Papers