A train 108 m long moving at a speed of 50 km/hr crosses a train 112 m long coming from opposite direction in 6 seconds. The speed of the second train is:

A.
48 km/hr
B.
54 km/hr
C.
66 km/hr
D.
82 km/hr

• 50km/hr=50*5/18
  =125/9 m/sec
  speed=distance/time
  (x+125/9)=(108+112)/6
  x=22.7 m/sec
  x=22.7*18/5 km/hr
  x=81.72 km/hr
  =82 km/hr
  
• 12 years agoHelpfull: Yes(2) No(0)
• Let the speed of the second train be x km/hr.
  
  Relative speed = (x + 50) km/hr
  =[(x + 50) x 5/18]m/sec
  =[250 + 5x]/18m/sec.
  Distance covered = (108 + 112) = 220 m.
  
  220/[(250 + 5x)/18]= 6
  
  250 + 5x = 660
  
  x = 82 km/hr.
• 11 years agoHelpfull: Yes(0) No(0)
• D.82 km/hr
  
  (108+112)/6=(50+x)*5/18
  .
  .
  .
  =82
• 7 years agoHelpfull: Yes(0) No(0)
• Let the speed of the second train be x km/hr.
  
  Relative speed = (x + 50) km/hr
  =[(x + 50) x 5/18]m/sec
  =[250 + 5x]/18m/sec.
  Distance covered = (108 + 112) = 220 m.
  
  220/[(250 + 5x)/18]= 6
  
  250 + 5x = 660
  
  x = 82 km/hr.
• 7 years agoHelpfull: Yes(0) No(0)