Question: 41 -

The speed of a train 150m long is 50kmph. How much time will it take to pass a platform 600m long? 

50 sec

54 sec

64 sec

60 sec

Answer:

54 sec

Solution:

Speed =(50 x 5/18) m/sec = 125/9 m/sec 

Required Time = 54 sec 

Question: 42 -

How much time will a train 171m long take to cross a bridge 229m long, if it is running at a speed of 45kmph? 

35 sec

32 sec

30 sec

40 sec

Answer:

32 sec

Solution:

Speed = 25/2 m/sec 

Required time = 32 sec 

Question: 43 -

A 120m long train takes 10 seconds to cross a man standing on a platform. The speed of the train is 

15 m/sec

20 m/sec

12 m/sec

10m/sec

Answer:

12 m/sec

Solution:

Speed = (120/10) m/sec = 12 m/sec

Question: 44 -

A train passes two persons walking in the same direction in which the train is going. These persons are walking at the rate of 3km/hr and 5km/hr respectively and the train passes them completely in 10 seconds and 11 seconds respectively. The speed of the train is 

28km/hr

27km/hr

25km/hr

24 km/hr

Answer:

25km/hr

Solution:

Let the length of the train be x km and it's speed be y km/hr 

Speed of the train relative to first man =(y-3)km/hr 

Speed of the train relative to second man = (y -5)km/hr 

=> Y-3 = 360x and 11y -55 =3600x 

=> 10y -30 = 3600x and 11y -55 = 3600x 

=> 10y -30 = 11y -55 

=> y = 25 

Therefore, Speed of the train = 25km/hr.

Question: 45 -

Two stations A and B are 110 kms apart on a straight line. One train starts from A at 7 a.m and travels towards B at 20km per hour speed Another train starts from B at 8 a.m. and travels towards A at a speed of 25 Km per hour at what time will they meet? 

10 a.m

none of these

9 a.m

11 a.m

Answer:

10 a.m

Solution:

Suppose they meet x hrs after 7 a.m 

Distance covered by A in x hrs = (20 × x) 

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

So they meet at 10 a.m.