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 5 of 8.
Shrif said:
1 decade ago
This answer will getting by converting the values of distance and cross multiplication to get this answer easily.
Rajivgandhi said:
2 decades ago
45x5/18 means (45x5)/18=225/18(divide by 9 both the numerator and dinominator).Then you will get the answer 25/2.
Rajivgandhi said:
2 decades ago
45 x 5/18 means (45 x 5)/18=225/18.
Then,
Divide by 9 both the Numerator and Dinominator.
Sure, u got Ans=25/2
Then,
Divide by 9 both the Numerator and Dinominator.
Sure, u got Ans=25/2
Venkatesh said:
1 decade ago
I don't get the reason for distance to be covered as 360+140 can any one suggest the reason with pleasure.
Saikiran said:
2 decades ago
45*5/18=25/2. I can't understand.
How you took 9 as a common number on both numerator and dinominator.
How you took 9 as a common number on both numerator and dinominator.
PraveenRaj said:
1 decade ago
I don't understand why in every problem they adding the train length also which they not asked. ?
Antony said:
2 decades ago
5/18 comes .because we want to express the unit of speed to m/s
1km/hr=1000m/3600s=5/18 m\s
1km/hr=1000m/3600s=5/18 m\s
Paddy said:
2 decades ago
5/18 comes .because we want to express the unit of speed to m/s
1km/hr=1000m/3600s=5/18 m\s
1km/hr=1000m/3600s=5/18 m\s
Syed khamar said:
10 years ago
S = 45*5/18 => 25/2.
Now train passes platform = 360+140/25/2.
= 500*2/25.
= 40 sec.
Now train passes platform = 360+140/25/2.
= 500*2/25.
= 40 sec.
Uzair said:
9 years ago
What about this?
What is the speed of a 140 m long train cross a 1 km bridge in 12 sec?
What is the speed of a 140 m long train cross a 1 km bridge in 12 sec?
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