In a flight of 600km ,an aircraft was slow down due to bad weather .its average speed for the trip was reduced by 200km/hr and the time increased by 30 minute..find the duration of the flight?

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are u sure?
yeah i am sure the time is 1 hr only
It is given in the ques..as flight of 600km
yeah i know
Yo thnks

Answers

2014-11-03T22:07:17+05:30
So distance = 600 km
let the speed be x km/hr
and
 time be t hr  = 600/x

now when it was delayed so speed now is (x - 200) km/hr
and time = t₁ = 600/(x- 200)
so according to the question

 t₁ - t = 1/2

600 (1/(x-200) - 1/x) = 1/2
⇒1200 (x - x + 200) = x² - 200x
⇒240000 = x² - 200x
x² - 200x - 240000 = 0
x² - 600x + 400x - 240000 = 0
x(x - 600) + 400(x = 600) = 0
(x - 600)(x + 400) = 0

so x = - 400 or 600 so speed can't be negative

so x = 600 km/hr 

So the time = 600/600 = 1 hr ANSWER
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yeah it is correct
Souvik118 is at higher rank, if he says so then it must be correct