A trucker calculates that if he increased his average speed by 90 km/h,he could travel his 660-km route in 7hr less time than his usual.Find his usual speed (km/h).

• (660/x)-(660/(x+90))=7
  solving we get
  x= 57.47 answer
  check- 660/57.47=11.47 hr
  660/(57.47+90)=4.47 hr
  difference is 7 hr
  
• 11 years agoHelpfull: Yes(44) No(1)
• Avg speed of truck = x and time = t
  usual eq 660 = xt
  and after increment in avg speed and decrement in time , the eq will be
  660 = (x+90)(t-7)
  Solving both eq x=20 and t=13
• 11 years agoHelpfull: Yes(14) No(7)
• let the avg speed be x,
  using the formula, distance/speed=time and
  then,acc to ques
  
  (660/x)-(660/(x+90))=7
  x=57.47 ans
• 11 years agoHelpfull: Yes(3) No(2)
• 55/6 km hr was his actual average speed.
  
  as
  
  avrage speed x= total dist/total time taken
  
  x=660/y
  
  new speed....
  
  x+90=660/y-7
  
  
• 11 years agoHelpfull: Yes(1) No(8)