In a flight of 600 km, an aircraft was slowed down due to bad weather. Its average speed for the trip was reduced by 200 km/hr and the time of flight increased by 30 minutes. The duration of the flight is:
(a) 1 hour
(b) 2 hours
(c) 3 hours
(d) 4 hours

• Ans: 1 hr
  Let the duration of the flight be x hours
  600/x - 600 (x+1/2)= 200
  600/x - 1200/(2x+1) = 200
  x(2x + 1) = 3
  2x2 + x - 3 = 0
  (2x + 3)(x - 1) = 0
  x can't be negative hence x=1
  x = 1 hr.
  Duration =1 hr
• 14 years agoHelpfull: Yes(13) No(1)
• answer should be 1.5 hours totally and originally 1 hour
  
  if time of journey originally is t hours then after delay it is t + (30/60) = t+1/2.
  distance is 600kms.
  speed originally is 600/t, so 600/t - 600/(t+1/2) = 200 since speed is said to be reduced by 200kmph .
  solving we get t=1hour
• 14 years agoHelpfull: Yes(5) No(1)
• 1 hour
• 14 years agoHelpfull: Yes(1) No(2)