Two trains travel in opposite directions at 36 kmph and 45 kmph and a man sitting in slower train passes the faster train in 8 seconds.The length of the faster train is
a)80 m b)100 m c)120 m d)180 m

• 
  Ans is 100 m
  Relative speed= 81 km/h
  = 81 x 5/18 m/sec
  =22.5 m/sec
  length of slower train= speed x time
  =36 x 8 km/hr
  =288 x 5/18 m/sec
  =80 m/sec
  Let length of faster train= b
  time cross to each other 8 = (80+b)x 18/(81 x 5)
  =3240-1440=18b
  1800/18= b
  b=100 m
• 11 years agoHelpfull: Yes(3) No(3)
• Ans is 180 m
  
  Relative Speed=(36+45)=81 km/h=81*5/18 m/sec= (45/2)m/sec
  Length of the train=(45/2)*8 m=180m
• 9 years agoHelpfull: Yes(2) No(0)