Two trains A and B start simultaneously from stations X and Y towards each other respectively. After meeting at a
point between X and Y,train A reaches station Y in 9 hours and train B reaches station X in 4 hours from the
time they have met each other. If the speed of trainA is 36 km/hr, what is the speed of train B?
a)24 km/hr b)54 km/hr c)81 km/hr d)16 km/hr

• it doesnt matter where it met.
  
  the total distance between X & Y is 9*36 km
  speed of B = (9*36)/4 = 81kmph is answer
• 9 years agoHelpfull: Yes(16) No(26)
• Let the Speed of train B is S and the time taken by both train to meet each other is T.
  so distance traveled by Train B before meeting and the distance traveled by train A after meeting is equal.
  So, T*S= 9*36
  so distance traveled by Train A before meeting and the distance traveled by train B after meeting is equal.
  So, T*S = T*36
  divide the both equation....
  Get the value of T=6h and S= 54 km/h.
  
• 9 years agoHelpfull: Yes(14) No(21)
• As we know the formula
  
  (A's speed):(B's speed)=b^(1/2) : a ^(1/2)
  
  let speed of the train B=x
  
  then according to the above formula
  
  36:X=4^(1/2):9^(1/2)
  
  =>x=54 km/hr
  hence
  
  B's speed = 54km/h (ans)
  
  
• 9 years agoHelpfull: Yes(13) No(2)
• Name the trains as A and B. Then,
  (A's speed) : (B's speed) = (b : a)^.5
  where b and a is the time taken by trains B and A resp. to reach their destination after they meet.
  hence,
  36/B's speed = (4: 9)^.5
  => B's speed = 54km/hr
• 9 years agoHelpfull: Yes(9) No(11)
• speed of B= Speed of A *[ (Time taken after 1st train meeting/Time taken by 2nd train after meeting)^1/2]
  
  therefore, Speed of B= 36*[(9/4)^1/2]
  
  =54 km/hr
• 9 years agoHelpfull: Yes(7) No(2)
• ans- 81 km/hr
  since we know speed = 1/time
  i.e. 9:4 = x:36
  => x = (9*36) / 4 = 81 km/hr
• 9 years agoHelpfull: Yes(3) No(4)
• d1=36*9
  =324
  s2=324/4
  =81 km/hr
• 9 years agoHelpfull: Yes(3) No(4)
• distance covered by train A in 1 hour=36km
  distance covered by train A in 9 hour=9*36km=324km
  now,same distance (324km)covered by train B=4hours
  so speed of train B=D/T=324km/4h=81km/h
  find
• 8 years agoHelpfull: Yes(3) No(3)
• given that trainA speed =36km/h
  and running time =9h
  distance bw X and Y station= 9*36=324km
  running time of train B=4h
  speed of train B = total distance / running time
  =324 / 4 = 81km/h
• 9 years agoHelpfull: Yes(2) No(9)
• D1=D2
  9*36=4*s2
  :. s2=81
  ans 81
• 9 years agoHelpfull: Yes(1) No(9)
• 81 km... is the ans
• 9 years agoHelpfull: Yes(1) No(6)
• here, t1:t2= 9:4
  hence s1:s2=4:9
  s1=36 i.e. 4*9=36
  and hence 9*p=81
  hence ans is 81
• 9 years agoHelpfull: Yes(1) No(4)
• we know that :
  s1/s2=t2/t1
  so that, 36/s2=4/9
  s2=9*9=81km/h
  
• 8 years agoHelpfull: Yes(1) No(3)
• ans d) 16 km/hr
• 7 years agoHelpfull: Yes(1) No(2)
• 54 km/hr is ans..
• 7 years agoHelpfull: Yes(1) No(1)
• all of u
  form mwt rule
  m w t
  20 1 12*8
  x+6+1 1 5*12
  20*1*12*8=x+6+1*5*12 find out x value
  simple a sweet
  
• 9 years agoHelpfull: Yes(0) No(0)
• As per formula
  A's speed : B's speed = sqrt(time taken by a):sqrt(time taken by B).
  So,
  Let x be speed of B
  Therefore,
  36:x = sqrt(9):sqrt(4)
  Solving for x we get,
  Answer = 24km/hr
• 9 years agoHelpfull: Yes(0) No(10)
• (9*36)/4=81 km/hr
• 5 years agoHelpfull: Yes(0) No(0)
• 
  X ---------------------------------- . ---------------------------------Y
  A-------> M (0)
  => d=((s2+36)/36) J-->(1)
  then A's takes 9 hrs to reach Y . Hence find distanc between M and Y
  9hrs X 36km/hr=324km
  d-J=324km =>(2)
  Applying (2) in (0) we get s2=11664/J =>(3)
  then distance travelled by B to reach X is equal to J
  J=s2 x 4
  J=11664/J*4 by solving we get J=216
  Thus s2=11664/216=54km/hr
  Thus 54km/hr is the right answer
• 4 years agoHelpfull: Yes(0) No(0)
• 
  X ---------------------------------- . ---------------------------------Y
  A-------> M (0)
  => d=((s2+36)/36) J-->(1)
  then A's takes 9 hrs to reach Y . Hence find distanc between M and Y
  9hrs X 36km/hr=324km
  d-J=324km =>(2)
  Applying (2) in (0) we get s2=11664/J =>(3)
  then distance travelled by B to reach X is equal to J
  J=s2 x 4
  J=11664/J*4 by solving we get J=216
  Thus s2=11664/216=54km/hr
  Thus 54km/hr is the right answer
• 4 years agoHelpfull: Yes(0) No(0)
• s1=9*36=324
  s2=324/4=81
  b=81 km/hr
• 4 years agoHelpfull: Yes(0) No(0)
• Let s1=36 km/hr, s2=?, t1=9 ,t2=4 hrs.
  
  if two trains A and B start from X and Y towards each other. After passing each other they take t1 and t2 time to reach Y and X respectively in s1 and s2 speed then, we have,
  
  s1/s2=√t2/t1
  
  so, by the above equation we have,
  
  36/s=√9/4
  so, 36/s=3/2
  s=36*2/3
  
  hence, s=24 is the correct answer.
• 3 years agoHelpfull: Yes(0) No(0)