A car travels a certain distance taking 7 hrs in forward journey, during the return journey increased speed 12km/hr takes the times 5 hrs. What is the distance traveled

(a) 210 kms (b) 30 kms (c) 20 kms (c) none of these

• If x is the distance, then
  difference in speeds =
  x/5 - x/7 = 12
  2x/35=12
  x= 12*35/2 = 210 kms.
• 13 years agoHelpfull: Yes(28) No(8)
• Given, car travel a certain distance in 7 hrs.
  let speed be x.
  so, by formula
  D = ST (D for distance , S for speed , T for time)
  D1 = 7x. -----------(statement 1)
  
  now for return journey
  Given, In return journey speed increased by12kmph.
  means , 12 + x (x is forward journey speed)
  time taken by car while returning back 5hrs
  so,
  D2 = ST
  D2 = (x+12)*5
  D2 = 5x+60 -----------(statement 2)
  
  from statement 1 & statement 2
  one thing is clear that in between distance of forward journey & retuning journey is same.
  whatever distance dist. cover by car in forward journey is as same as covered in backward journey.
  
  what we get,
  5x+60 = 7x
  60 = 2x
  x = 30
  
  ANS : 30km.
• 11 years agoHelpfull: Yes(14) No(26)
• a)210 km's
  
  i.e the equation will be 7hrs*x = (x+12)*5hrs
  by solving that the fwd journey speed comes to 30km/hr.
  hence distance is 7*30= 210 kms
• 13 years agoHelpfull: Yes(9) No(7)
• the correct answer is 420 kms so option d is the right choice that is NONE OF THESE...
  it is as follows if the distance from source to destination is D then total distance covered will be 2D
  let speed be x
  hence
  7*x=(x+12)*x
  i.e x=30km/hr
  D=7*30=210km
  2D=420kms
• 13 years agoHelpfull: Yes(6) No(4)
• the correct answer is 420 kms so option d is the right choice that is NONE OF THESE...
  it is as follows if the distance from source to destination is D then total distance covered will be 2D
  let speed be x
  hence
  7*x=(x+12)*5
  i.e x=30km/hr
  D=7*30=210km
  2D=420kms
• 13 years agoHelpfull: Yes(6) No(3)
• distance is same
  let the speed is x
  then x*7=(x+12)*5
  2x=60
  x=30km/hr
  so the distance b/w two point=30*7=210km
• 13 years agoHelpfull: Yes(2) No(3)
• If x is the distance, then
  difference in speeds =
  x/5 - x/7 = 12
  2x/35=12
  x= 12*35/2 = 210 kms.
• 13 years agoHelpfull: Yes(2) No(2)
• let X km/hr be the speed and D be the distance in forward journey
  given,
  7*X=D----eq(1)
  5*(X+12)=D---eq(2)
  equating eq(1) and eq(2) we get
  7X=5X+60
  X=30 km/hr
  so the distance traveled is (30*7) 210 kms
• 13 years agoHelpfull: Yes(1) No(5)
• a) 210km
  
  x*7 = (x+12)*5
  x=30 km/hr
  
  30*7= 210km
• 13 years agoHelpfull: Yes(1) No(3)
• answer is 30 km
• 9 years agoHelpfull: Yes(1) No(1)
• let x be the distance traveled.
  y be the speed of the car.
  then to travel x distance 7*y equal to 5*(y+12)
  7y=5y+60,y=30 then x=7*30=210.
  
  
• 13 years agoHelpfull: Yes(0) No(2)
• let take d distance traveled is x. so (x/7 + 12)5 = x
  (speed=dist/time) so x=210
• 13 years agoHelpfull: Yes(0) No(3)
• 7x=(x+12)5
  x=30,d=7*30=210
• 13 years agoHelpfull: Yes(0) No(4)
• answer is option a. because when car goes forward takes 7 hours and when comes back takes 5 hours according to this the velocity is 30 kmph for forward journey and 42kmph for return. so the distance will be 210kms
• 13 years agoHelpfull: Yes(0) No(4)
• let for forward journey v1=velocity, d1=distance, t1=time & for return journey
  v2=velocity, d2=distance,t2= time
  here v2=v1+12; d1=d2 & t1=7 hrs, t2=5 hrs,
  as d1=d2
  v1*t1=v2*t2
  7*v1=5*(v1+12)
  7*v1=5*v1+60
  v1=30
  & therefore d1=d2=v1*t1=30*7=210 kms
• 13 years agoHelpfull: Yes(0) No(3)
• 7x=(x+12)5
  2x=60
  x=30
  total distance=7x=210 kms
  
• 10 years agoHelpfull: Yes(0) No(1)
• miss dhanlakshmi u hve solved out the question is totally wrong u assume the variable x as speed then how could u answer it same as the distance travelled
  
• 9 years agoHelpfull: Yes(0) No(0)
• from the first part we conclude that:s=d/7(s =speed,d=total distance)....eq1
  from second part s+12=d/5................eq2
  after solving both equation we get d=210..hence optio A is correct
• 9 years agoHelpfull: Yes(0) No(1)
• Let forward speed =v km/hr
  return speed=v+12 km/hr
  now distance will same so
  7v=(v+12)5
  v=30 km/hr
  distance=30*7=210 kms
• 6 years agoHelpfull: Yes(0) No(0)
• x/5 - x/7 = 12
  2x/35=12
  x= 12*35/2 = 210 kms.
• 5 years agoHelpfull: Yes(0) No(0)
• If x is the speed and y is the distance, then
  
  x=y/7 -----(1)
  
  x+12=y/5
  
  x=y/5-12 -----(2)
  
  from (1) and (2)
  
  y/7=y/5-12
  
  y/5-y/7=12
  
  2y=35*12
  
  y=35*6
  
  y=210 kms
• 5 years agoHelpfull: Yes(0) No(0)