<PRE><B>Question 275377</B>
It takes 1.5 hrs to fly 600km against the wind. 
distance = 600 km ; time = 1.5 hrs ; rate = 600/1.5 = 400 km/hr
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The return trip with the wind takes only 1hr. 
distance = 600 km ; time = 1 hr. ; rate = 600 km/hr
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Find the total flying time for the round trip if there was no wind.
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Find rate of the plane in still air:
p + w = 600 km/hr
p - w = 450 km/hr
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2p = 1050
p = 525 km/hr (speed of the plane in still air)
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Flying time for the round trip with no wind:
time = distance /rate
time = 1200 km/525 km/hr = 2.286 hrs = 2 hr (0.286)60 min = 2 hr 17 min
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Cheers,
Stan H.</PRE>