Two trains each 414 meter long, are running in opposite directions on parallel tracks. If their spee

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02 Mar 2017 Time taken

Two trains each 414 meter long, are running in opposite directions on parallel tracks. If their speeds are 39 km/hr and 69 km/hr respectively, the time taken by the slower train to pass the driver of the faster one is?

OPtion

1) 12.8 seconds
2) 13.4 seconds
3) 13.8 seconds
4) 14.4 seconds
5) 14.8 seconds
6) 27.6 seconds
7) 28.0 seconds
8) 28.8 seconds
9) 29.5 seconds
10)22.0 seconds

Solution

Relative speed= 39+69 = 108 km/hr = 108 * 5/18 = 30 m/sec

We are calculating the time taken by the slower train to pass the driver of the faster one.
Hence, distance = length of the slower train = 414 metre

Time = 414/30 = 13.8 seconds

Option 3)

Correct Option: 3 Best Solution (11)

Dr.Dipin Singh   7 years AGO

Relative speed= 39+69=108 km/hr= 30m/sec
Time taken by 414 m long train to pass other driver = 414/30= 13.8 secs

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sudhir saurav   7 years AGO

relative speed=(39+69)km/hr
=(108*5/18)m/s
=30 m/s
we have to find the time taken by the slower train to pass the driver of the faster train and not the complete train.
so, distance covered=length of the slower train
therefore,distance covered=414m
required time=(414*1/30)sec=13.8 sec

Like? Yes (2) | No (1)  

Devendra Marghade   7 years AGO

Relative speed=39+69=108 km/hr
Time taken by slower train to pass the driver of the faster train=Time taken to cross the distance of 414 m or 0.414 km with the relative speed.
=0.414/108 hr or (0.414/108)x3600=13.8 sec
Option 3)

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Azim Uddin Siddiqui   7 years AGO

since they r moving in opp directions, relative speed is 69+39=108kmph , which is 108*1000/3600=30m/s
time taken = distance/speed= 414/30=13.8 Seconds

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Harsh Poddar   7 years AGO

Speed of slower train relative to faster train is 39+69=108=30 m/s
Time taken by slower train to cross the driver of faster train = (length of slower train)/(relative speed)
=414/30=13.8 sec

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Kannan Ravi   7 years AGO

Trains Travelling in Opposite Direction then speed=speed1 + speed2 =108km/hr

convert to m/s by multiplying 5/18
108*5/18 =30m/s

T=D/S =414/30 =13.8 seconds

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Mukund Manohar   7 years AGO

Relative Speed = 39+69 = 108 km/hr = 30m/s
Distance Covered = Length of Slower Train = 414 m
Required Time = Distance/Speed = 414/30 = 13.8 seconds

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BASUKI KESHRI   7 years AGO

since train are moving in opposite direction so relative speed will be addition of speed of two train, so s= 108 and d = 414 since in the question it said time taken by slower train to pass the driver of faster train.

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somveer   7 years AGO

Two trains A and B speed is 39(5/18)m/s and 69(5/18)m/s resp.
Both the trains length 414 m
So, (A+B)t=length
(39(5/18)+69(5/18))t=414
now t=13.8 second

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Baishali Roy   7 years AGO

The trains are running in the opposite direction. So, the relative speed is= (39+69) km/hr=108km/hr=30m/s
Now, each train is of 414meters.
so, the time taken by the first train to pass the driver of the second train is equivalent to the time taken by first train to pass 414mts.
That is: 414/30 sec.=13.8 s (Ans). (Opt 3).

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Naga   7 years AGO

Distance to cross D = 414
Collective speed of the train V = 39+69 KM/hr
= 108*1000/(60*60) = 30 m/s
TIME to cross driver of the fast train =
414/30 = 13.8s

Like? Yes | No (2)