Three friends A, B and C live in Patiputra. They want to go to see the neighboring city Kalinga which is 150 km away from Patiputra but they have only one bike which can move at the speed of 40 km/hr. Each one of them can walk at the speed of 8 km/hr. (Only two people can travel by the bike at a time) What is the minimum time taken to reach to Kalinga if they used the best way to go

• A and B by motorcyle to patliputra in 225 min(150/40*60)
  during this time C will travel 225*8/60=30km
  
  now A WILL ASK B TO GET DOWN AT PATLIPUTRA and will come back to collect C. for C distance to be covered is 150-30 = 120 km
  
  suppose C and A meets at x distance from Cs present position and hthey meet at time t
  so x/8=(120-x)/40 this gives x=20 and time t= 20/8*60 min= 150 minutes
  now A and C can ride remaining 100 km on motorcycle with 40 kmph in 150 min
  so total time is 225+150+150=525 min=8 hr 45 min
• 8 years agoHelpfull: Yes(0) No(1)