One persont travlled 4 laps with the speed of 10,20,40 ( or 30) and 60 kmph and what is the average speed.

• total distance=x+x+x+x=4x
  total time=x/10+x/20+x/40+x/60
  avg speed=4x/(x/10+x/20+x/40+x/60)=20
• 9 years agoHelpfull: Yes(6) No(0)
• Let the lap be x km
  Time taken by him to cover 4x km
  =x/10 +x/20 +x/30 +x/60 hrs
  =12x/60 hrs
  =x/5 hrs
  Therefore average speed
  =4x divided by x/5
  =4x*5/x
  =20 kmph
  
• 9 years agoHelpfull: Yes(6) No(0)
• avg speed=total distance/total time
  let distance=d
  avg speed=(d+d+d+d)/(d/10+d/20+d/40+d/60)
  =4d*120/23d=480/23
• 11 years agoHelpfull: Yes(1) No(3)