problems on trains.35

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PROBLEMS ON TRAINS 1. A train 150 m long is running at a speed of 90kmph. Time taken by the train to cross a tree is : Answer :6 Difficulty Level : Easy Moderately easy Difficult Basic Formula: Time = Answer with Explanation: Speed of the train = 90 kmph = 90 x = 25 m/sec. Distance to cross the tree = Length of the train = 150 m. Require time = = 6 sec. Problems on Trains, BU Page 1 www.aptitudecoach.com

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Page 1: Problems on Trains.35

PROBLEMS ON TRAINS

1. A train 150 m long is running at a speed of 90kmph. Time taken by

the train to cross a tree is :

Answer :6

Difficulty Level : Easy Moderately easy Difficult

Basic Formula:

Time =

Answer with Explanation:

Speed of the train = 90 kmph = 90 x = 25 m/sec.

Distance to cross the tree = Length of the train

= 150 m.

Require time = = 6 sec.

Problems on Trains, BU Page 1 www.aptitudecoach.com

Page 2: Problems on Trains.35

2. A train 280m long, running with a speed of 63kmhr will pass a pole in:

Answer:12

Difficulty Level : Easy Moderately easy Difficult

Basic Formula:

Time :

Answer with Explanation:

Speed of the train = 63 km/hr = 63 x = m/secDistance to pass the pole = Length of the train

= 280 m.

Required time = = 16 sec.

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Page 3: Problems on Trains.35

3. A train is moving at speed of 132kmph. If the length of the train is

110 meters, how long will it take to cross a railway platform 165 m long?

Answer :7.5

Difficulty Level : Easy Moderately easy Difficult

Basic Formula:

Time :

Answer with Explanation:

Speed of the train = 132 kmph = 132 x = m/sDistance covered in passing the platform

= Length of the train + Length of the Platform= (110 + 165) = 275 m.

Required time = = 7.5 sec.

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Page 4: Problems on Trains.35

4. In what time will a train 100 meres long cross an electric pole, if its speed is 144 km/hr?

2.5 seconds         4.25 seconds   5 seconds       12.5 seconds 

Difficulty Level : Easy Moderately easy Difficult

Basic Formula:

Time :

Answer with Explanation:

Speed of the train = 144 x = 40 m/sec.Distance covered in passing the electric pole

= Length of the train = 100 m.

Required time = = 2.5 sec.

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Page 5: Problems on Trains.35

5. 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?

40 sec                        42 sec             45 sec              48 sec 

Difficulty Level : Easy Moderately easy Difficult

Basic Formula:

Time :

Answer with Explanation:

Speed of the train = 45 x = m/sec.Distance covered in passing the bridge

= Length of the train + Length of the bridge = 360 + 140 = 500 m

Required time = = 40 sec..

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Page 6: Problems on Trains.35

6. The ratio between the speeds of two trains is 7 : 8. If the second train runs 400 kms in 4 hours, then the speed of the first train is:

70 km/hr         75 km/hr         84 km/hr          87.5 km/hr

Difficulty Level : Easy Moderately easy Difficult

Basic Formula:

Speed =

Answer with Explanation:

Given V1 : V2 = =

Given V2 = = 100 km/h.

= V1 = = 87.5 km/hr.

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Page 7: Problems on Trains.35

7. An express train traveled at an average speed of 100 km/hr, stopping for 3

minutes after every 75 km.. How long did it take to reach its destination 600

km from the starting point?

6 hrs 21min     6 hrs 24 min    6 hrs 27 min       6 hrs 30 min

Difficulty Level : Easy Moderately easy Difficult

Basic Formula:

Time :

Answer with Explanation:Speed of the train = 100 km hr.Distance = 600 km.

Time taken = = 6 hrs.

Given the train stops for 3 minutes after every 75 km.

No. of stoppings = = 8Omitting the last stopping No. of stoppings = 7Time taken at one stop = 3 min.

Time taken for 7 stops = 7 x 3 = 21 min. Total time taken to reach the destination = 6 hrs 21 min.

Problems on Trains, BU Page 7 www.aptitudecoach.com

Page 8: Problems on Trains.35

8. A goods train runs at the speed of 72 km/hr and crosses a 250 m long platform in 26 seconds. What is the length of the goods train?

230 m                           240 m            260 m          270 m 

Difficulty Level : Easy Moderately easy Difficult

Basic Formula:

Distance = Speed x Time

Answer with Explanation:

Length of the train = x m.Speed of the train = 72 km hr = 72 x

= 20 m/secTime taken = 26 sec.Length of the Platform = 250 m.

Total Length = (x + 250) m. (x+250) = 20 x 26 = 520

x+250 = 520

x = 270

Length of the train = 270 m.

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Page 9: Problems on Trains.35

9. A train covers a distance of 10 km in 12 minutes. If its speed is decreased by 5 km/hr the time taken by it to cover the same distance will be:

10 min           11 min 20 sec             13 min         13 min 20 sec

Difficulty Level : Easy Moderately easy Difficult

Basic Formula:

Speed = , Time =

Answer with Explanation:Given, Distance = 10 km.Time = 12 min. = = hr.

Speed = = 50 kmphr.If the speed of the train is decreased by 5 kmphrNew Speed = 50-5 = 45 kmphr.Distance = 10 km.

Time taken = = hrs.

= x 60 = = 13.33 min. ( .33 min. = .33 x 60 sec. = 19.9 sec.)

=13 min. 20 sec.

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Page 10: Problems on Trains.35

10. A train passes a station platform in 36 seconds and a man standing on the platform in 20 seconds. If the speed of the train is 54 km/hr, what is the length of the platform?

120 cm                  240 cm              300 cm              110 cm 

Difficulty Level : Easy Moderately easy Difficult

Basic Formula:

Distance = Speed x Time

Answer with Explanation:

To find the length of the train : Length of the train = xSpeed of the train = 54 km/hr = 54 x = 15 m/sec.Time taken to cross the man = 20 sec.

Length of the train = 15 x 20 = 300 m.

To find the Length of the Platform : -

Length of the platform = ymTime taken to cross the platform = 36 sec. Total distance covered = Length the train + length of the platform

= 300 + y

300 + y = 54 x x36 =540 300 + y = 540 y = 240 m.

Length of the platform = 240 m.

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Page 11: Problems on Trains.35

11. A train 280 m long is moving at 60kmph. The time taken by the train to cross a tunnel 220 m long is: Answer: 30

Difficulty Level : Easy Moderately easy Difficult

Basic Formula:

Time =

Answer with Explanation:Speed of the train = 60 x = m/sec.Distance covered in passing the tunnel

= Length of the train + Length of the tunnel = 280 + 220 = 500 m.

Time taken = = 30 sec.

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Page 12: Problems on Trains.35

12. With a speed of 60kmph a train crosses a pole in 30 seconds. The length of the train is: Answer : 500

Difficulty Level : Easy Moderately easy Difficult

Basic Formula:

Distance = Speed x Time

Answer with Explanation:

Speed of the train = 60 x = m/s.Time taken = 30 sec.

Distance = x 30 = 500 m.

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Page 13: Problems on Trains.35

13. A train traveling at a speed of 90kmph crosses a pole in 10 seconds. The length of the train is:

Answer : 250

Difficulty Level : Easy Moderately easy Difficult

Basic Formula:

Distance = Speed x Time

Answer with Explanation:Speed of the train = 90 x = 25 m/sec.Time taken = 10 sec.

Distance = 25 x 10 = 250 m.

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Page 14: Problems on Trains.35

14. A train 120 m long crosses a standing man in 15 seconds. The speed of the train is: Answer: 28.8

Difficulty Level : Easy Moderately easy Difficult

Basic Formula:

Speed =

Answer with Explanation:

Distance = 120 m.Time = 15 sec. Speed = = 8 m/sec.

= 8 x = 28.8 km/hr

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Page 15: Problems on Trains.35

15. A train 700 m long is running at 72kmph. If it crosses a tunnel in I minute, the length of the length of the tunnel is: Answer: 500

Difficulty Level : Easy Moderately easy DifficultBasic Formula:

Distance = Speed x Time

Answer with Explanation:

Speed of the train = 72 km/hr = 72 x = 20 m/sec.Time taken = 1 min. = 60 sec.Length of the train = 700 m.Length of the tunnel = x m

Total length = (700 + x) m. (700 + x) = 20 x 60

700 + x = 1200 x = 500

Length of the tunnel = 500 m.

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Page 16: Problems on Trains.35

16.The length of a brigade which a train 130 m long and traveling at 45kmph can cross in 30 seconds, is: Answer: 245

Difficulty Level : Easy Moderately easy Difficult

Basic Formula:

Distance = Speed x Time

Answer with Explanation:

Speed of the train = 45 x = m/sec.Time = 30 sec.

Length of the train = 130 m.Length of the bridge= x m

Total Length = (130 + x) m (130 +x) = x 30

130 + x = 375

x =375 – 130 x = 245 m.

Length of the bridge = 245 m.

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Page 17: Problems on Trains.35

17. If a 200 m long train crosses a platform of the same length as that of the train in 20 seconds, then the speed of the train is: Answer: 72

Difficulty Level : Easy Moderately easy Difficult

Basic Formula:

Speed =

Answer with Explanation:Length of the train = Length of the Platform = 200 m.

Total length = 200 + 200 = 400 mTime taken = 20 sec.

Speed = = 20 m/s

= 20 x = 72 km/hr.

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Page 18: Problems on Trains.35

18. A train 60 m long passes a platform 90 m long in 10 seconds. The speed of the train is: Answer: 54

Difficulty Level : Easy Moderately easy Difficult

Basic Formula:

Speed =

Answer with Explanation:Length of the train = 60 m.Length of the Platform = 90 m.

Total Distance covered = 60 + 90 = 150 m.Time taken = 10 sec.

Speed = = 15 m/sec.

= 15 x = 54 km/hr.

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Page 19: Problems on Trains.35

19. A train 300 m long crossed a platform 900 m long in 1 minute 12 seconds. The speed of the train (in km/hr) is:

Answer: 60

Difficulty Level : Easy Moderately easy Difficult

Basic Formula:

Speed =

Answer with Explanation:Length of the train = 300 m.Length of the Platform = 900 m.Total Distance covered = 300 + 900 = 1200 m.Time taken = 1 min. 12 sec. = 72 sec.

Speed = = m/sec.

= x = 60 km/hr.

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Page 20: Problems on Trains.35

20.A train crosses a platform 100 m long in 60 seconds at a speed of 45kmph. The time by the train to cross an electric pole is: Answer: 52 sec

Difficulty Level : Easy Moderately easy Difficult

Basic Formula:

Distance = Speed x Time, Time =

Answer with Explanation:To find the length of the train :-

Speed of the train = 45 x = m/sec.Length of the train = x mLength of the Platform = 100 m.

Total distance covered = (x + 100) mTime = 60 sec.

100 + x = x 60 100 + x = 750 x = 650 m.

Length of the train = 650 m.

To find the time taken to cross the pole:-

Distance covered = Length of the train = 650 m. Required Time = = 52 sec.

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Page 21: Problems on Trains.35

21.A train of length 150 m long takes 40.5 seconds to cross a tunnel of length 300 m the speed of the train(in km/hr) is:Answer: 40

Difficulty Level : Easy Moderately easy Difficult

Basic Formula:

Speed =

Answer with Explanation:

Length of the train = 150 m.Length of the tunnel = 300 m.

Total Distance covered = 150 +300 = 450 m.Time taken = 40.5 sec.

Speed = x = 40 km/hr.

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Page 22: Problems on Trains.35

22.A train 150 m long takes 20 seconds to cross a platform 450 m long. The speed of the train(in m/sec) is: Answer: 30

Difficulty Level : Easy Moderately easy Difficult

Basic Formula:

Speed =

Answer with Explanation:

Length of the train = 150 m.Length of the Platform = 450 m.

Total Distance covered = 450 +150 = 600 m.Time taken = 20 sec.

Speed = = 30 m/s.

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Page 23: Problems on Trains.35

23.A train speeds past a pole in 15 seconds and a platform 100 m long in 25 seconds. Its length is: Answer: 150

Difficulty Level : Easy Moderately easy Difficult

Basic Formula:

Speed =

Answer with Explanation:To find the speed while crossing the Platform:-

Length of the train = x m.Length of the Platform = 100 m.

Total Distance covered = (100 + x) mTime taken = 25 sec.

Speed = __________________ 1

To find the speed while crossing the Pole:-

Distance covered = Length of the train = x mTime taken = 25 sec.

Speed = ________________________ 2

1 = 2 = 15 (100+x) = 25 x

x = 150 m..

Length of the train = 150 m.

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Page 24: Problems on Trains.35

24. A train takes 18 seconds to pass completely though a station162 m long and 15 seconds though another station 120 m long. The length of the train is:Answer: 90

Difficulty Level : Easy Moderately easy Difficult

Basic Formula:

Speed =

Answer with Explanation:To find the speed while crossing the First Station:-

Length of the train = x m.Length of the First Station = 162 m.

Total Distance covered = (x+162) mTime taken = 18 sec.

Speed = __________________ 1

To find the speed while crossing the Second Station:-Length of the Second Station = 120 m.

Total Distance covered = (x+120) mTime taken = 15 sec.

Speed = ___________________2

1 = 2 = 15 (x+162) = 18 (x+120)

x = 90 m..

Length of the train = 90 m.

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Page 25: Problems on Trains.35

25. If a train 110 m long passes a telegraph pole in 3 seconds, then the time taken by it to cross a railway platform 165 m long is: Answer: 7.5

Difficulty Level : Easy Moderately easy Difficult

Basic Formula:

Speed = , Time =

Answer with Explanation:

To find the speed of train while crossing the Pole:-

Length of the train = 110 m. Time taken = 3 sec.

Speed = m/sec.

To find the time taken while crossing the Platform:-

Length of the Platform = 165 mTotal Distance covered = 110 + 165 = 275 mSpeed of the train = m/s

Time taken = = 7.5 sec.

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Page 26: Problems on Trains.35

26. A train 110 m long is traveling at a speed of 59kmph. The time in which it will pass a passer by, walking at 4kmph in the same directions, is: Answer: 71/3

Difficulty Level : Easy Moderately easy Difficult

Basic Formula:Time =

Answer with Explanation:Speed of the train = 59 km/hr.Speed of the man = 4 km/hr.Since both are in the same direction Relative speed = (59-4) = 55 km/hr.Length of the train = 110

Time = =

Time = 7 sec.

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Page 27: Problems on Trains.35

27.A train 150 m long moving at a speed of 35 meters per second overtakes a man moving at 5 meters/sec in opposite direction. The train will pass the man in: Answer: 5

Difficulty Level : Easy Moderately easy Difficult

Basic Formula:

Time =

Answer with Explanation:Speed of the train = 35 m/sSpeed of the man = 5 m/sSince both are moving in opposite direction Relative speed = (35+5) = 40 m/sec.Length of the train = 150 m

Time = = 3.75 sec.

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Page 28: Problems on Trains.35

28.Two trains each 200 m long are running on parallel rails at the rate of 40kmph and 45kmph respectively. In how much time will they cross each other, if they are running in the same direction? Answer: 288

Difficulty Level : Easy Moderately easy Difficult

Basic Formula:

Time =

Answer with Explanation:Distanced covered = Total length of the two trains

= 200 + 200 = 400 m.Speed of the First train = 40 kmph.Speed of the Second train = 45 kmph.Since both the trains are moving in the same directionRelative speed = 40-45 = 05 kmph.Relative speed = 5x = m/s

Time taken = = 288 sec.

Problems on Trains, BU Page 28 www.aptitudecoach.com

Page 29: Problems on Trains.35

29.Two trains 126 m and 114 m long are running in opposite directions, one at the rate of 30kmph and another one at 42kmph. From the moment they meet will cross each other in: Answer: 12

Difficulty Level : Easy Moderately easy Difficult

Basic Formula:

Time =

Answer with Explanation:

Distance covered = Total length of the two trains = 126 + 114 = 240 m.

Speed of the First train = 30 kmph.Speed of the Second train = 42 kmph.Relative speed = (30+42) = 72 kmph.

= 72 x = 20 m/sec.

Time taken = = 12 sec.

Problems on Trains, BU Page 29 www.aptitudecoach.com

Page 30: Problems on Trains.35

30.A train 270 m long is moving at a speed of 24kmph. It will cross a man coming form the Opposite direction at a speed of 3kmph, in: Answer: 36

Difficulty Level : Easy Moderately easy Difficult

Basic Formula:

Time =

Answer with Explanation:

Length of the train = 270 m.Distance covered = Length of the train = 270 m.Speed of the train = 24 kmph.Speed of the man = 3 kmphSince the train and the man are moving in opposite direction Relative speed = (24+3) = 27 kmph

= 27 x = m/sec.

Required Time = = 36 sec.

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Page 31: Problems on Trains.35

31.A train 125 m long passes a man, running at 5 kmph in the same direction

in which rate train is going in 10 seconds. The speed of the trains is :

Answer : 50

Difficulty Level : Easy Moderately easy Difficult

Basic Formula:

Relative Speed =

Answer with Explanation:

Length of the train = 125 m.Time taken = 10 sec.

Speed of the train = x kmphSpeed of the man = 5 kmphSince the train and the man are moving in the same direction Relative speed = (x – 5) x m/sec.

(x -5) = x-5 = 45

x = 50 m/s.

Speed of the train = 50 m/sec.

Problems on Trains, BU Page 31 www.aptitudecoach.com

Page 32: Problems on Trains.35

32. A train 110 m long passes a man, running at 6 kmph in the direction

opposite tot hat of the train, in 6 secs. The speed of the train is

Answer : 60

Difficulty Level : Easy Moderately easy Difficult

Basic Formula:

Relative Speed =

Answer with Explanation:

Length of the train = 110 m

Time taken = 6 sec.

Speed of the train = x kmph

Speed of the man = 6 kmph

Since the train and the man are moving in the opposite direction

Relative speed = (x +6) x m/sec.

(x +6) x = x+6 = 66

x = 60 m/sec.

Speed of the train = 60 m/sec.

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Page 33: Problems on Trains.35

33. A train overtakes two persons who are walking in the same direction in

which the train is going, at the rate of 2 kmph and 4 kmph and passes them

completely in 9 and 10 seconds respectively. The length of the train is :

Answer: 50

Difficulty Level : Easy Moderately easy Difficult

Basic Formula:

Relative speed =

Answer with Explanation: Length of the train = x m

Speed of the train = S kmph.

To find the relative speed of the train crossing the first man :-

Speed of the First man = 2 kmph., Time = 9 sec.

Relative speed = (S-2) m/sec.

(S-2) x = S = +2 ______________ 1

To find the relative speed of the train crossing the second Man:-

Speed of the second man = 4 kmph, Time = 10 sec.

Relative speed = (S-4) x m/sec.

(S-4) x = S = +4 ______________ 2

1 = 2 +2 = +4 x = 50 m. Length of the train = 50 m.

Problems on Trains, BU Page 33 www.aptitudecoach.com

Page 34: Problems on Trains.35

34. Two stations A and B are 110 km apart on a straight line. One train starts

from A at 7 am and towards B at 20 kmph. Another train starts from B at 8

am and travels towards A at a speed of 25 kmph. At what time will they

meet?

Answer : 10 am

Difficulty Level : Easy Moderately easy Difficult

Basic Formula:

Distance = Speed x Time

Answer with Explanation:

Suppose the two trains meet x hrs after 7 am

Distance covered by A in x hrs = 20 x x km.

Distance covered by B in (x-1) hrs = 25 (x-1) km.

Given distance between the two stations = 110 km.

20 x + 25 (x-1) = 110

45 x = 135

x = 3 hrs.

The two trains meet at 10 am.

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