. Person travels from A to B with speed of 4kmph and returns back from B with speed of 5 km/h, what is his average speed of journey?

• 2*xy/(x+y)=2*4*5/(4+5)=4.4
• 12 years agoHelpfull: Yes(19) No(0)
• Average speed = total distance/ total time.
  Total distance is 2d
  and total time is d/4+d/5=9d/20.
  2d X 20/9d=40/9=4.44 (its NOT 4.5)
• 12 years agoHelpfull: Yes(12) No(0)
• A to B=4kmph
  B to A=5kmph
  i.e
  total dist=2x
  total time=(x/4)+(x/5)=9x/20
  total speed=total dist/total time
  s=2x/(9x/20)
  s=4.444
  
  avg=4.44
  
• 12 years agoHelpfull: Yes(3) No(0)
• avg speed=2*4*5/9=4.44
• 12 years agoHelpfull: Yes(2) No(0)
• it can be calculated by simple formula 2xy/x+y
  2*5*4/9 = 4.44
• 12 years agoHelpfull: Yes(2) No(0)
• 2*4*5/4+5=4.44
  2xy/x+y=?
• 12 years agoHelpfull: Yes(1) No(0)
• 4.5km/h becouse
• 12 years agoHelpfull: Yes(0) No(3)