two trains each 100m long moving in opposite direction cross each other in 8 seconds if one is moving twice as fast as other then the speed of faster train is?

• Ans= 60 km/hr
  Let the speed of slow train=x and fast train=2x
  Distance covered=100+100=200 meters, with the speed=x+2x=3x
  Time=200/3x=8 sec ->x=25/3 m/s
  Therefore fast train speed=2x=50/3 m/s=50*3600/3*1000=60 km/hr
  
• 12 years agoHelpfull: Yes(20) No(0)
• Answer : 60km/hr
  Let speed of Slower train be x m/s
  speed of Faster train be 2x m/s
  Relative speed = x+2x = 3x m/s
  S = d / t
  3x = (100+100)/8 -------> train moving in opposite direction so + ..
  on solving,
  24x = 200
  x= 25/3
  speed of faster train = 2x = 2*(25/3) = 50/3 m/s
  converting m/s to km/hr = (50/3)*(18/5) = 60km/hr..
  
• 12 years agoHelpfull: Yes(14) No(0)
• speed of the second train is 50/3 m/sec
  trains length=100+100=200
  time=8m/s
  first train sped=x second train speed=2x total=3x
  then 200/3x=8then x=25/3 and 2x=50/3 i.erequired ans.
  
• 12 years agoHelpfull: Yes(2) No(3)