Q. A man is 20 mins late to the office if he walks at 20 kmph, and 15 mins earlier if he walks at 30 kmph. How much time will he be early/late if he walks at 25 kmph?

• let distance be x,then
  time1= x/20*60,
  t2=x/30*60
  difference b/w both time is 35min then
  x/20-x/30=35 so x=35
  now for 25kmph
  35/25*60= 84 min
  for 20kmph time=105 min
  for 30kmph time= 70min
  in 30 kmph he is early by 15 min then actual time is 85 min
  so the anser is he is early by 1 min
  ans=early 1 min
  t=35/25*60
• 11 years agoHelpfull: Yes(22) No(4)
• Let us assume x= Exact time
  
  According to the given condition
  the time for 20 kmph is (20+x)min and for 30 Kmph (x-15)min
  
  We know that Speed = Distance/Time
  Distance = 20(20+x) ........>(1)
  Distance = 30(x-15) ........>(2)
  
  Equating Eqn (1) and (2),we get
  20(20+x) = 30(x-15)
  x=85 min
  The Exact time is 85 min.
  
  Substitute x value in eqn (1),
  Distance = 35 Km
  
  The Time for 25 Kmph is = (35/25)60 = 84 min.
  
  But the exact time is 85 min.
  
  S0, he is early by 1min.
  
  
• 11 years agoHelpfull: Yes(18) No(0)
• It would be early by a minute.
  
  Let distance be a meter ,but as time is in minutes,
  
  t1 = a / 20*60 (for converting to minutes from hour)
  
  Similarly,
  t2 = a / 30*60
  
  Difference between time is 20 minutes late + 15 minutes earlier = 35 minutes
  So,
  a/20-a/30=35
  
  so,a = 35
  
  
  Then for 25 kmph,
  
  t3 = 35 / 25*60 = 84 minutes
  t1 = 105 minutes
  t2 = 70 minutes
  
  so while in 30 kmph, man is early by 15 minutes,so actual time to travel is 85 minutes.
  
  So, to find what is current delay or early arrival,
  
  85-t3 = 85 - 84 = 1 minute earlier
  
  So, answer is 1 minute early
• 11 years agoHelpfull: Yes(6) No(2)
• let distance be x,then
  time1= x/20*60,
  t2=x/30*60
  difference b/w both time is 35min then
  x/20-x/30=35 so x=35
  will get x(dist)/60=35
  x=35*60=2100
  total distance is 2100
  we need to find time=distance/speed
  so he walks 25kmph time=2100/25=84
  ans=84
  
  
• 11 years agoHelpfull: Yes(3) No(0)
• one minute early....
• 11 years agoHelpfull: Yes(1) No(0)
• early by one minute
  
• 11 years agoHelpfull: Yes(0) No(1)
• 1 min earlier..
• 11 years agoHelpfull: Yes(0) No(1)
• 1 min early
• 10 years agoHelpfull: Yes(0) No(0)