1. A train running at 30 km/hr takes 24 seconds to cross a platform. It takes 8 seconds to pass a man
walking towards it at 6 km/hr. Find the length of the train and of the platform.
1) 200 metres 2) 120 metres 3) 220 metres 4) 320 metres 5) None of these
Solution: (5). Distance = length of Train + Length of Platform
Convert all units to metres & Seconds
Platform crossed in 24 seconds
Then Distance = length of train + length of platform
= speed x time
= 30 km X 24 sec
= 30 X 5/18 x 24
Length of Train & Platform = 200
Man crossed in 8 seconds
Distance = length of train
= speed x time (speed = train +man)
= 36 x 5/18 x 8
Length of train = 80 m
Then platform = 200 – 80 = 120 m
2. Two trains are moving in the same direction at 75 km/hr and 48 km/hr. The faster train crosses a
man sitting in the slower in 14 seconds. Find the length of the faster train .
1) 105 metres 2) 115 metres 3) 125 metres 4) 120 metres 5) None of these
Solution: (1).Same direction = relative speed
= faster – slower
= 75 – 48
Relative speed
Time to cross
Length of faster train
= 27 k/hr
= 14 seconds
= speed x time
= 27 km x 14 sec
= 27 x 5/18 x 14
= 105 metre
3. A 175 metre long train crosses a 35 metre platform in 12 seconds. What is the speed of the train in
Km/hr?
1)42 2)64 3)63 4)59 5)None of these
Solution (3). Speed = Distance / Time
[ Distance = Train +platform = 175 + 35 = 210 m ]
= 210 m / 12 sec
= 210/12
x 18/5 km/hr
= 63 km/hr
4. A train covers a distance of 180 km in 4 hours. Another train covers the same distance in one hour
less. What is the difference in the distance covered by these two trains in one hour?
1) 45 km 2) 40 km 3) 15 km 4) 9 km 5) None of these
Solution: (3).Distance covered by the first train in 1 hour
= 180 / 4 = 45 km
Distance covered by the second train in 1 hour = 180/3 = 60km
Therefore required difference = ( 60 - 45)km = 15km
5. A train takes 3 hours to run from one station to another . If it reduces its speed by 12 km/hr, it takes
45 minutes more for the journey . The distance between the station is
1) 220 km 2) 210 km 3) 180 km 4) 160 km 5) None of these
Solution: (3).let the distance between the stations be x km
Original speed = x/3. km/hr
New speed = [ (x/3 ) – 12) km/hr
New time = 3 hrs + 45 minutes = 3 ¾ hrs = 15/4 hrs
Therefore [ (x/3) – 12 ] * 15/4 = x
Or, (5/4) x - 45 =x
Or ,x/4 = 45
Or, x = 180 km
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