a train has crossed a tunnel of length 340 m in 42 sec, another tunnel of length 500m in 50 sec then find the speed of train.

• let x be length of the train
  or (340+x)/42=(500+x)/50
  or x= 500m
  speed of train=(500+500)/50=20m/s
• 7 years agoHelpfull: Yes(5) No(0)
• 340+length of train (x) in 42 sec. (Equation 1).
  500+length of train(x) in 50 sec (Equation 2).
  solve 1 and 2
  x=500 m
• 7 years agoHelpfull: Yes(0) No(1)
• Speed of train is 72 km / h ... L+340=42s
  L+500=50s .solve this two equation u get s=72 km /, h
• 7 years agoHelpfull: Yes(0) No(2)
• Difference b/w two tunnel = (500 - 340) = 160 m
  Difference b/w Passing Time = (50 - 42) = 8 sec
  
  So, 160 m is equivalent to 8 sec => 20 m is equivalent to 1 sec
  So, Total distance => 42 * 20 = 840 or 50 * 20 = 1000
  So , Train length => 840 - 340 = 500 or 1000 - 500 = 500 (same in each case)
  
  So, Speed of the Train = 840 / 42 = 20 m/s = 72 km/hr or 1000 / 50 = 20 m/s = 72 km/hr (Ans)
• 5 years agoHelpfull: Yes(0) No(1)
• let speed of train = y km/h
  let the lenght of train = x
  42y = 340 +x ....eq1
  50y = 500 +x...eq 2
  sloving 1&2
  8y =160
  y = 20km/h
• 4 years agoHelpfull: Yes(0) No(1)