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Bunuel
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Two trains are traveling in the same direction at 50 kmph and 30 kmph. 03 Jan 2020, 02:25
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74% (01:58) correct 26% (02:17) wrong based on 172 sessions

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Two trains are traveling in the same direction at 50 kmph and 30 kmph. The faster train crosses a man sitting in the slower train in 18 seconds. Find the length of the faster train.

A. 80 mts
B. 100 mts
C. 120 mts
D. 125 mts
E. 150 mts
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B
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Stonely
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Two trains are traveling in the same direction at 50 kmph and 30 kmph. 03 Jan 2020, 13:40
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we are talking about relative speed 50-30=20kph
20000m/h*1h/60min*1min/60sec
200/36=5.555555m/s
5.55555 m/s*18 s=99.999999 meters

the guy timing must have had a shaky finger and miss timed just a little ;)
answer is B
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Two trains are traveling in the same direction at 50 kmph and 30 kmph. 04 Jan 2020, 11:00
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Relative speed =(50-30) = 20 kmph
= 20(5/18) msec

Distance = 20*(5/18) * 18 meter
= 20*5
= 100 meter(B)
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Two trains are traveling in the same direction at 50 kmph and 30 kmph. 06 Nov 2020, 04:51
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Jawad001
Relative speed =(50-30) = 20 kmph
= 20(5/18) msec

Distance = 20*(5/18) * 18 meter
= 20*5
= 100 meter(B)
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where do you get the 5 in 20(5/18) from?
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Two trains are traveling in the same direction at 50 kmph and 30 kmph. 12 Apr 2021, 04:54
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The faster train goes 50 - 30 = 20 kmph faster than the slower train. In other words, if the slower train stands still (i.e. speed =0), the faster train travels at 20 kmph.

In 3600 seconds the faster train travels 20,000 meters

In 18 seconds the faster train travels (20,000 X 18)/ 3600 = 100 meters.

Option: B.
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Two trains are traveling in the same direction at 50 kmph and 30 kmph. 14 Apr 2021, 11:29
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Stonely
we are talking about relative speed 50-30=20kph
20000m/h*1h/60min*1min/60sec
200/36=5.555555m/s
5.55555 m/s*18 s=99.999999 meters

the guy timing must have had a shaky finger and miss timed just a little ;)
answer is B
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-------------------------------------------

But why are we calculating the relative speed when we just want to find out the length of the faster train wrt the man?

It can simply be: (50*1000*18)/(3600)?
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Two trains are traveling in the same direction at 50 kmph and 30 kmph. 24 Mar 2024, 17:35
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