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

View Answer

Correct Answer :
1 hour

Explanation :

Let the duration of the flight be x hours

Then, (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 = 1 hr (neglecting the -ve value of x)

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