Two trains move in the same direction at speeds 50 kmph and 32 kmph respectively. A man in the slower train observes that 15 seconds elapse before the faster train completely passes by him. What is the length of faster train?
(a) 100m
(b) 75m
(c) 120m
(d) 50m

• Answer : (b)
  
  Since both trains are moving in the same direction their relative speed is 50-32 kmph = 18kmph = 5m/s
  Now speed*time = distance which will give length of faster train
  So, 15s*5m/s = 75m
• 13 years agoHelpfull: Yes(11) No(1)
• As both train are moving in the same direction,
  so,
  their relative speed = 50 -32 = 18 km/h
  which is equal to 5 m/s
  now,
  length of aster train is speed*time
  which is 15*5 = 75 m
• 9 years agoHelpfull: Yes(1) No(0)
• relative speed(moving in same direction) = 50 -32 = 18 kmph
  18 kmph = 18 * 5/18 m/s
  so distance = speed * time
  5 * 15
  75 m
  option b
• 9 years agoHelpfull: Yes(0) No(0)