A man traveled from the village to the post-office at the rate of 25 kmph and walked back at the rate of 4 kmph. If the whole journey took 5 hours 48 minutes, find the distance of the post-office from the village.

• Ans:- 20km
  
  Solution:-
  Average speed = 2ab/(a+b) here a=25 b=4
  = 2x25x4/(25+4)=200/29 km/hr.
  Distance covered in 5 hours 48 minutes
  = Speed x time = (200/29)x (29/5) Distance covered in 5 hours 48 minutes = 40kms
  Distance of the post office from the village = (40/2)=20 km.
• 9 years agoHelpfull: Yes(23) No(6)
• x/25 + x/4 = 29/5
  so x= 20 km
• 9 years agoHelpfull: Yes(12) No(0)
• (d/25)+(d/4)=(29/5)
  d=20kms
• 9 years agoHelpfull: Yes(2) No(0)
• (x/25)+(x/4)=29/4
  =>29x/100=29/4
  =>x=20
• 9 years agoHelpfull: Yes(2) No(0)
• distance is same so average speed = 2xy/(x+y)
  speed=2*25*4/(25+4)=200/29
  distance=speed*time
  total distance=(200/9)*(29/5)=>40kms
  postoffice to villageIs=40/2=>20kms
• 9 years agoHelpfull: Yes(2) No(1)
• 20km
  
  4 x 5 = 20
  25 x 0.8 = 20
  therefore total time taken = 5hr + 0.8hr = 5hr 48min
  so the distance is 20km
• 9 years agoHelpfull: Yes(0) No(2)
• 20 km..
  is the ans.
• 9 years agoHelpfull: Yes(0) No(2)
• The average speed of whole journey = (2*25*4/(25+4)) =6.89 km/h = 1.9138 m/s
  Time taken for whole journey = 5h 48 m = 20880 seconds
  
  1.9138 = (distance/20880)
  distance = 39.96 km
• 9 years agoHelpfull: Yes(0) No(2)
• let distance is d
  d/4+d/25=5+(48/60)
  solve and get d=20
  so total distance is 20*2=40
• 9 years agoHelpfull: Yes(0) No(0)
• 40km
  relative speed=distance /time
• 9 years agoHelpfull: Yes(0) No(0)
• Ans=20km
  
  Solution:-
  
  suppose time take while going to post office=x min
  time taken while returning=y min
  speed=25/60 km/min
  distance covered in x min =5x/12 km
  speed while returning=4/60 km/min
  distance covered in y min=y/15 km
  
  both the ditance are same...
  so, (y/15)=(5x/12)
  we get 75x=12 y.......(i)
  
  total time taken is x+y=348 min .....(ii)
  on solving (i),(ii) we get x=48 min.
  by putting it in (5x/12) we get x=20km.
• 9 years agoHelpfull: Yes(0) No(0)
• answer is 20 as forward speed is 25kmph and return speed is 4kmph and total time tkn is 5hr48min dat is 29/5 hrs so ..... total distance is equal to (total time)*(product of speeds)/(adddition of speeds)
• 9 years agoHelpfull: Yes(0) No(0)
• 24 km...............
• 8 years agoHelpfull: Yes(0) No(0)
• 20km
  x/25 + x/4 = 29/5
  so x= 20 km
• 8 years agoHelpfull: Yes(0) No(0)
• Ans:20 km
  Let the distance from village to post office be x
  x/25+x/4=5+48/60
  x=20
• 7 years agoHelpfull: Yes(0) No(1)
• 28 km
  distance in going = distance in coming
  25*t1(time to go)=4*t2(time to come back)
  and also t1+t2= 5hour 48 min
  solving both we get distance=20km
• 7 years agoHelpfull: Yes(0) No(0)
• 20km
  
  4 x 5 = 20
  25 x 0.8 = 20
  therefore total time taken = 5hr + 0.8hr = 5hr 48min
  so the distance is 20km.
• 7 years agoHelpfull: Yes(0) No(1)
• Ans 2 km
  X/25 + x/4 = 348/60
• 7 years agoHelpfull: Yes(0) No(0)
• average speed=2xy/x+y then 2*25*4/25+4= 200/9 km/hr and dist travelled is 5 4/5 hrs.
  so total (200/9*29/5)=40km then dist travelled from post office to village is 40/2=20km
• 7 years agoHelpfull: Yes(0) No(0)
• let the distance be d
  d/25+d/4=5+4/5
  d=20
• 4 years agoHelpfull: Yes(0) No(0)
• Avg speed =2xy/x+y
  =2*25*4/25+4
  =200/29
  time=5+48/60
  =29/5
  D = 200/29*29/5
  D = 40 km
• 4 years agoHelpfull: Yes(0) No(1)