A cow was standing on a bridge, 5m away from middle of the bridge. A train was coming towards the bridge from the end nearest to the cow. seeing this the cow ran towards the train and managed to escape when the train was 2m away from the bridge. if it had run in the opposite direction (i.e away from the train ) it would have been hit by the train 2m before the end of the bridge , what is the length of the bridge in metres assuming speed of train is 4 times that of the cow?
Option
a. 32
b. 36
c. 40
d. Can't b detrmnd

• |...|........|....|.......|...|........|
  2 x-2 M 5 C x-5 2 a T
  
  where M,T,C are Middle point and Train location and Cow location
  
  1st:
  Train distance=a
  cow distance=x-5
  Time taken by both is same let it be=t1
  Given train speed(Ts)=4*Cow speed(Tc)
  we have
  a/t1=4*(x-5)/t1
  20=4x-a --------------eq 1
  
  case 2:
  Train distance=a+2+x+x-2=2x+a
  cow distance=5+x-2=3+x
  Time taken by both is same let it be=t2
  Given train speed(Ts)=4*Cow speed(Tc)
  we have
  2x+a/t2=4(3+x)/t2
  2x+a=12+4x
  -12=2x-a ----------------eq 2
  solve equations to get x=16
  so lenght of bridge is 2x= 32
• 10 years agoHelpfull: Yes(25) No(3)
• Answer = 32
  Let x be the length of the bridge. Let x' be the distance of the train from the bridge end nearest to the cow. Let y be the speed of the train. Then spped of cow is y/4.
  
  ((x/2)-5)/(y/4) = (x'-2)/y (i) and
  
  
  ((x/2)+3)/(y/4)= (x'+x-2)/y (ii)
  
  Solving i and ii we get x=32
• 10 years agoHelpfull: Yes(25) No(0)
• Let the length of bridge be 2x and the
  train is coming from an end at a distance of y from one end of the bridge.
  Let the speed of the cow is c
  then speed of the train will be 4c.
  
  Now the time taken by the cow to escape from bridge and time taken by train to reach at first point will be equal
  i.e.,
  (x-5)/c=(y-2)/4c
  =>4x-y=18
  Now again the time taken by the train to hit the cow and time taken by cow to reach at second point will be equal
  i.e.,
  (5+x-2)/c=(y+x+x-2)/4c
  =>2x-y=15
  solving both the eq we will get the value of 2x as 32 that is the required answer.
• 10 years agoHelpfull: Yes(8) No(1)
• Let the length of bridge be 2x and the
  train is coming from an end at a distance of y from one end of the bridge.
  Let the speed of the cow is c
  then speed of the train will be 4c.
  
  Now the time taken by the cow to escape from bridge and time taken by train to reach at first point will be equal
  i.e.,
  (x-5)/c=(y-2)/4c
  =>4x-y=18
  Now again the time taken by the train to hit the cow and time taken by cow to reach at second point will be equal
  i.e.,
  (x+5)/c=(y+x+x-2)/4c
  =>2x-y=-22
  solving both the eq we will get the value of 2x as 40 that is the required answer.
• 10 years agoHelpfull: Yes(3) No(4)
• |...|........|....|.......|...|........|
  2 x-2 M 5 C x-5 2 a T
• 10 years agoHelpfull: Yes(1) No(1)
• Solution:
  Answer is 32.
  Assuming that trains speed is 4 times that of the cow.
  When the cow travels for 11 meters, the train wood travel 44(11*4) meters.
  And when it travels for 19(in the opposite direction) meters (i.e 32-2-11) the train wood travel 76(19*4) meters in total.
  i.e., 19*4=76=>
  44m+2m+30m
• 10 years agoHelpfull: Yes(1) No(0)
• answer will be 32
• 10 years agoHelpfull: Yes(0) No(0)
• ans is not 32 its 40
  
• 10 years agoHelpfull: Yes(0) No(2)
• final ans is 32 only.....no more confusion.
• 10 years agoHelpfull: Yes(0) No(0)