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- Question
A 300 metre long train crosses a platform in 39 seconds while it crosses a signal pole in 18 seconds. What is the length of the platform?
Options- A. 320 m
- B. 350 m
- C. 650 m
- D. Data inadequate
- Correct Answer
- 350 m
ExplanationSpeed = ❨ 300 ❩ m/sec = 50 m/sec. 18 3 Let the length of the platform be x metres.
Then, ❨ x + 300 ❩ = 50 39 3 ⟹ 3(x + 300) = 1950
⟹ x = 350 m.
- 1. A train speeds past a pole in 15 seconds and a platform 100 m long in 25 seconds. Its length is:
Options- A. 50 m
- B. 150 m
- C. 200 m
- D. Data inadequate Discuss
- 2. A train moves past a telegraph post and a bridge 264 m long in 8 seconds and 20 seconds respectively. What is the speed of the train?
Options- A. 69.5 km/hr
- B. 70 km/hr
- C. 79 km/hr
- D. 79.2 km/hr Discuss
- 3. Two trains are running at 40 km/hr and 20 km/hr respectively in the same direction. Fast train completely passes a man sitting in the slower train in 5 seconds. What is the length of the fast train?
Options- A. 23 m
- B. 23 2⁄9
- C. 27 7⁄9
- D. 29 m Discuss
- 4. A train overtakes two persons walking along a railway track. The first one walks at 4.5 km/hr. The other one walks at 5.4 km/hr. The train needs 8.4 and 8.5 seconds respectively to overtake them. What is the speed of the train if both the persons are walking in the same direction as the train?
Options- A. 66 km/hr
- B. 72 km/hr
- C. 78 km/hr
- D. 81 km/hr Discuss
- 5. How many seconds will a 500 metre long train take to cross a man walking with a speed of 3 km/hr in the direction of the moving train if the speed of the train is 63 km/hr?
Options- A. 25
- B. 30
- C. 40
- D. 45 Discuss
- 6. A train travelling at a speed of 75 mph enters a tunnel 3½ miles long. The train is ¼ mile long. How long does it take for the train to pass through the tunnel from the moment the front enters to the moment the rear emerges?
Options- A. 2.5 min
- B. 3 min
- C. 3.2 min
- D. 3.5 min Discuss
- 7. Two trains are running in opposite directions with the same speed. If the length of each train is 120 metres and they cross each other in 12 seconds, then the speed of each train (in km/hr) is:
Options- A. 10
- B. 18
- C. 36
- D. 72 Discuss
- 8. A 270 metres long train running at the speed of 120 kmph crosses another train running in opposite direction at the speed of 80 kmph in 9 seconds. What is the length of the other train?
Options- A. 230 m
- B. 240 m
- C. 260 m
- D. 320 m
- E. None of these Discuss
- 9. Two trains are moving in opposite directions @ 60 km/hr and 90 km/hr. Their lengths are 1.10 km and 0.9 km respectively. The time taken by the slower train to cross the faster train in seconds is:
Options- A. 36
- B. 45
- C. 48
- D. 49 Discuss
- 10. Two trains of equal lengths take 10 seconds and 15 seconds respectively to cross a telegraph post. If the length of each train be 120 metres, in what time (in seconds) will they cross each other travelling in opposite direction?
Options- A. 10
- B. 12
- C. 15
- D. 20 Discuss
Problems on Trains
Search Results
Correct Answer: 150 m
Explanation:
Let the length of the train be x metres and its speed by y m/sec.
| Then, | x | = 15 ⟹ y = | x | . |
| y | 15 |
| ∴ | x + 100 | = | x |
| 25 | 15 |
⟹ 15(x + 100) = 25x
⟹ 15x + 1500 = 25x
⟹ 1500 = 10x
⟹ x = 150 m.
Correct Answer: 79.2 km/hr
Explanation:
Let the length of the train be x metres and its speed by y m/sec.
| Then, | x | = 8 ⟹ x = 8y |
| y |
| Now, | x + 264 | = y |
| 20 |
⟹ 8y + 264 = 20y
⟹ y = 22.
| ∴ Speed = 22 m/sec = | ❨ | 22 x | 18 | ❩ | km/hr = 79.2 km/hr. |
| 5 |
Correct Answer: 27 7⁄9
Explanation:
| Relative speed = (40 - 20) km/hr = | ❨ | 20 x | 5 | ❩ | m/sec = | ❨ | 50 | ❩ | m/sec. |
| 18 | 9 |
| ∴ Length of faster train = | ❨ | 50 | x 5 | ❩ | m = | 250 | m = 27 | 7 | m. |
| 9 | 9 | 9 |
Correct Answer: 81 km/hr
Explanation:
| 4.5 km/hr = | ❨ | 4.5 x | 5 | ❩ | m/sec = | 5 | m/sec = 1.25 m/sec, and |
| 18 | 4 |
| 5.4 km/hr = | ❨ | 5.4 x | 5 | ❩ | m/sec = | 3 | m/sec = 1.5 m/sec. |
| 18 | 2 |
Let the speed of the train be x m/sec.
Then, (x - 1.25) x 8.4 = (x - 1.5) x 8.5
⟹ 8.4x - 10.5 = 8.5x - 12.75
⟹ 0.1x = 2.25
⟹ x = 22.5
| ∴ Speed of the train = | ❨ | 22.5 x | 18 | ❩ | km/hr = 81 km/hr. |
| 5 |
Correct Answer: 30
Explanation:
| Speed of the train relative to man | = (63 - 3) km/hr | |||||||
| = 60 km/hr | ||||||||
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| ∴ Time taken to pass the man |
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| = 30 sec. |
Correct Answer: 3 min
Explanation:
| Total distance covered |
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| ∴ Time taken |
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| = 3 min. |
Correct Answer: 36
Explanation:
Let the speed of each train be x m/sec.
Then, relative speed of the two trains = 2x m/sec.
| So, 2x = | (120 + 120) |
| 12 |
⟹ 2x = 20
⟹ x = 10.
| ∴ Speed of each train = 10 m/sec = | ❨ | 10 x | 18 | ❩ | km/hr = 36 km/hr. |
| 5 |
Correct Answer: 230 m
Explanation:
Relative speed = (120 + 80) km/hr
| = | ❨ | 200 x | 5 | ❩m/sec |
| 18 |
| = | ❨ | 500 | ❩m/sec. |
| 9 |
Let the length of the other train be x metres.
| Then, | x + 270 | = | 500 |
| 9 | 9 |
⟹ x + 270 = 500
⟹ x = 230.
Correct Answer: 48
Explanation:
Relative speed = (60+ 90) km/hr
| = | ❨ | 150 x | 5 | ❩m/sec |
| 18 |
| = | ❨ | 125 | ❩m/sec. |
| 3 |
Distance covered = (1.10 + 0.9) km = 2 km = 2000 m.
| Required time = | ❨ | 2000 x | 3 | ❩sec = 48 sec. |
| 125 |
Correct Answer: 12
Explanation:
| Speed of the first train = | ❨ | 120 | ❩ | m/sec = 12 m/sec. |
| 10 |
| Speed of the second train = | ❨ | 120 | ❩ | m/sec = 8 m/sec. |
| 15 |
Relative speed = (12 + 8) = 20 m/sec.
| ∴ Required time = | [ | (120 + 120) | ] | sec = 12 sec. |
| 20 |
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