train travelled from A to B and back in time at rate 60k/hr but if trainb had travelled from A to B at rate of 80k/hrn back from B to A at rate of 40k/hr it would have 2 hrs llonger find distance between A n B

• Ans=480 Kms.
  Let the distance between A & B=x
  For first case time to travel distance=2x/60 hr.
  For second case time to travel distance=x/80 +x/40 =3x/80
  Given 3x/80 -2x/60 = 2 so x=480 Kms.
• 11 years agoHelpfull: Yes(34) No(2)
• Ans = 480
  
  In this question we have two case
  1. let Av. speed for first time= 60 km/hr
  2. in second case , find av speed between two = 2 *80*40/(40+80) = 160/3
  
  now it is given that it takes 2 hr long
  
  let distance = x
  3x/160 - x/60 = 2
  by solving we have
  x= 960. since 960 is two way distance, so distance between A to B or B to A is 960/2 =480
• 11 years agoHelpfull: Yes(6) No(1)
• ANS : 480 kms
  Let x be the distance b/w A & B.
  Then,
  from case 1 : speed = distance/time
  or time T1 = distance/speed
  T1 = 2x/60 = x/30
  Similarly,
  from case 2 : T2 = t1+t2 = x/80 + x/40
  
  T2-T1 = x/80 + x/40 - x/30 = 2 (given)
  (x/10)(1/8 + 1/4 -1/3) = 2
  (x/240)(3+6-8) = 2
  x = 2*240 = 480
• 10 years agoHelpfull: Yes(2) No(1)
• let distance from A to B = D
  then total distance travelled by train at the rate of 60k/hr=2D
  and time time taken by it is X
  then 2D/60=X;
  =D/30=X-----------------(1)
  and
  in same way
  D/80+D/40=X+2-----------------(2)
  put value of X in eq (2) by (1)
  D/80+D/40=(D/30) + 2
  D/10(1/8+1/4-1/3)=2
  D/10(1/24)=2;
  D/240=2;
  D=480;
• 11 years agoHelpfull: Yes(1) No(1)
• Let x be the distance b/w A & B.
  Then,
  from case 1 : speed = distance/time
  or time T1 = distance/speed
  T1 = 2x/60 = x/30
  Similarly,
  T2 = t1+t2 = x/60 + x/40
  
  T2-T1 = x/60 + x/40 - x/30 = 2 (given)
  (x/10)(1/6 + 1/4 -1/3) = 2
  (x/120)(2+3-4) = 2
• 10 years agoHelpfull: Yes(1) No(0)
• May be i am Wrong.. but you guys have read the book so much that you become blind.. i think ans. is 160 km.
  
• 10 years agoHelpfull: Yes(1) No(10)
• let distance between a and b =x
  time for a=2x/60
  time for b=x/80+x/40
  give 3x/80=(x/30)+2
  3x=8x/3 + 160
  x/3 = 160
  x=480
• 10 years agoHelpfull: Yes(1) No(0)
• Answer will be: 480km
  Reason being: T1+2=T2
  T1=(2*x)/60 and T2=(x/80+x/40)
  Solving for x, we get 480km
• 11 years agoHelpfull: Yes(0) No(0)
• ANS : 240 kms
  Let x be the distance b/w A & B.
  Then,
  from case 1 : speed = distance/time
  or time T1 = distance/speed
  T1 = 2x/60 = x/30
  Similarly,
  from case 2 : T2 = t1+t2 = x/60 + x/40
  
  T2-T1 = x/60 + x/40 - x/30 = 2 (given)
  (x/10)(1/6 + 1/4 -1/3) = 2
  (x/120)(2+3-4) = 2
  x = 2*120 = 240
• 10 years agoHelpfull: Yes(0) No(2)
• Let the distnc is x;
  (x/80+x/60)-2x/60=2
  x=480km
• 9 years agoHelpfull: Yes(0) No(0)