Two trains 121 m and 99 m in length respectively are running in opposi

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Competition Mode Question

Two trains 121 m and 99 m in length respectively are running in opposite directions, one at the rate of 40 kmph and the other at the rate of 32 kmph. How long will they take to be completely clear of each other from the moment they meet?

A. 110 sec
B. 99 sec
C. 88 sec
D. 77 sec
E. 11 sec

A. 110 sec
B. 99 sec
C. 88 sec
D. 77 sec
E. 11 sec

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ArunSharma12 · Answer

when the two trains meet each other distance between them = 121 + 99 = 220 m
relative speed of two trains =  \frac{(40 + 30)*5}{18}  mps
time to cross each other =  \frac{220}{20} = 11s
Ans: E

eakabuah · Answer

At the point when the two trains start to pass each other, the trains will be 121+99=220m apart. We need to find the time taken to cover the distance of 220m traveling at the relative speeds of the two trains. Relative speed=32+40=72

time taken in seconds = 3600*0.22/72 = 72*11/72 = 11seconds.

E is the right answer.

time taken in seconds = 3600*0.22/72 = 72*11/72 = 11seconds.

E is the right answer.

freedom128 · Answer

At t secs, Train #1 travelled (5/18*40*t) meter and Train #2 travelled (5/18*32*t) meter.

If the tail of both trains coincides one another at t secs, then:
(5/18*40*t)+(5/18*32*t) = 121+99=220 m --> t=11 secs

FINAL ANSWER IS (E)

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exc4libur · Answer

distance between them: 
121+99m=220m
220/1000km=22/100km

relative direction towards:
add rates=40+32=72kmh

time to pass each other:
(22/100)/72kmh=11/100*36kmh
11*60*60secs/(100*36)=11secs

Ans (E)

shameekv1989 · Answer

Total Distance to be covered = 121+99 = 220 meters
Relative Speed = 40+32 = 72 kmph = \frac{(72*1000)}{3600} = 20 m/s

Time = \frac{Distance}{Speed}  =  \frac{220}{20}  = 11 secs

Answer - E

Archit3110 · Answer

total distance = 121+99 ; 220 m
and relative speed ; 40+32 ; 72kmph
72*5/18 ; 20 m/sec
so net time when they cross each other ; 220/20 ; 11 sec
IMO E

Two trains 121 m and 99 m in length respectively are running in opposite directions, one at the rate of 40 kmph and the other at the rate of 32 kmph. How long will they take to be completely clear of each other from the moment they meet?

A. 110 sec
B. 99 sec
C. 88 sec
D. 77 sec
E. 11 sec

A. 110 sec
B. 99 sec
C. 88 sec
D. 77 sec
E. 11 sec

unraveled · Answer

Two trains 121 m and 99 m in length respectively are running in opposite directions, one at the rate of 40 kmph and the other at the rate of 32 kmph. How long will they take to be completely clear of each other from the moment they meet?

A. 110 sec
B. 99 sec
C. 88 sec
D. 77 sec
E. 11 sec

A. 110 sec
B. 99 sec
C. 88 sec
D. 77 sec
E. 11 sec

If we start with option C and check whether length of train is 220m(121m+99m)
Rel. Speed = 32 + 40 = 72kmph = 20m/s
So, in 88 sec distance covered = 20*88 = 1760m which is too long

Hence we go towards E the most likely answer.

ELSE

Total distance = 121 + 99 = 220m 
Since trains are running in opposite directions relative Speed with which they cross each other = 32 + 40 = 72kmph =  72*\frac{1000}{3600}  m/s
 Time taken = \frac{Distance}{Speed} = \frac{220*3600}{72*1000}  = 11sec

Answer E.

firas92 · Answer

When the two trains meet, the end points are at distance of  121+99=220m  or  \frac{220}{1000}km

These two end points move towards each other at a rate of  40+32=72kmph  or  \frac{72}{3600}kmps

So  \frac{72}{3600}*  Time taken  =\frac{220}{1000}

Time taken  =\frac{220}{1000}*\frac{3600}{72}=11seconds

Answer is  (E)

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sal8 · Answer

d/s= t

121+99= 220metres

40 + 32 = 72kph

0.22/72= 11/3600

11/3600 hours = 11 seconds

lacktutor · Answer

Two trains 121 m and 99 m in length respectively are running in opposite directions, one at the rate of 40 kmph and the other at the rate of 32 kmph. How long will they take to be completely clear of each other from the moment they meet?

A. 110 sec
B. 99 sec
C. 88 sec
D. 77 sec
E. 11 sec

1st train:  40  kmph=  \frac{40000}{3600}= \frac{100}{9}  meter per second.
2nd train:  32  kmph=  \frac{32000}{3600}= \frac{80}{9}  meter per second.
--------------------------------------------------
when they meet each other, the distance between the endings of the trains will be  220  meters
The question is when those edges of the trains meet???

121+ 99= (\frac{100}{9}+\frac{80}{9})*t 
-->  t = \frac{220}{20} =11  seconds

Answer (E).

effatara · Answer

Actually, given the answer choices, it is immediately obvious that only E is the logical answer because any of the other options would take the trains far, far away from each other. For example, as per Option D, the slower train would have traveled (80/9)mps*99secs=880 meters and the faster train (100/9)*99=1100 meters.

Anyway, doing the math:
Time taken for the trains to be completely clear of each other = (sum of their lengths)/(sum of their speeds) = 220/20 = 11 secs.

Anyway, doing the math:
Time taken for the trains to be completely clear of each other = (sum of their lengths)/(sum of their speeds) = 220/20 = 11 secs.

piyush0122 · Answer

Total distance the trains have to cover=121+99=120m
speed of first train in m/s= 40*(5/18)=100/9 m/s
speed of second train in m/s=32*(5/18)=80/9 m/s
Relative speed of the two trains = (100/9)+(80/9)=180/9 m/s=20 m/s
time= distance/speed= 220/20=11sec

ScottTargetTestPrep · Answer

The two trains will be completely clear of each other after they travel a distance that is equal to the sum of their body lengths. Therefore, if we let t = the number of hours it takes the two trains to be completely clear of each other, we can create the equation:

40t + 32t = 121/1000 + 99/1000

72t = 220/1000

72t = 0.22

t = 0.22/72

Since it takes 0.22/72 hours for the trains to be clear of each other, the number of seconds to do this is:

0.22/72 x 3600 = 0.22 x 50 = 11

Answer: E

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Two trains 121 m and 99 m in length respectively are running in opposi

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