person completes a journey in 15 hours, the first half at 12 kmh
"1 and the second half at 18
kmh
"1
. What is the total distance

• (x/2)/12 + (x/2)/18 = 15
  or
  (3x+2x)/72 = 15
  or
  x=216 km
• 9 years agoHelpfull: Yes(2) No(0)
• Let total distance be x
  x/2 is covered at 12 kmph and remaining x/2 at 18kmph
  distance / speed = time
  x/(2*12) + x/(2*18) = 15
  x/24 + x/36 = 15
  (3x+2x)/72 = 15
  5x/72 =15
  x = 15*72/5
  = 216km
  
  
  
• 9 years agoHelpfull: Yes(0) No(0)
• total time is 15 hr.
  let total distance is x km.
  So,
  15=x/24 + x/36
  =>x=216
  So, total distance is 216 km
• 9 years agoHelpfull: Yes(0) No(0)
• average speed=(2*S1*S2)/(S1+S2)
  on solving,avg speed=72/5
  total distance=72/5*15=216
• 9 years agoHelpfull: Yes(0) No(0)