SOLUTION: an air rescue plane averages 300 miles per hour in still air. It carries enough fuel for 5 hours of flying time. If, upon takeoff it encounters a head wind of 30 mi/hr and the wind

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Question 125596: an air rescue plane averages 300 miles per hour in still air. It carries enough fuel for 5 hours of flying time. If, upon takeoff it encounters a head wind of 30 mi/hr and the wind remains constant, how far can the plane fly and then return safely.
Answer by ankor@dixie-net.com(22740) About Me  (Show Source):
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an air rescue plane averages 300 miles per hour in still air. It carries enough fuel for 5 hours of flying time. If, upon takeoff it encounters a head wind of 30 mi/hr and the wind remains constant, how far can the plane fly and then return safely.
:
The outbound speed: 300 - 30 = 270 mph
The return speed: 300 + 30 = 330 mph
:
Let d = distance to the point of no return
:
Write a time equation: Time = distance%2Fspeed
:
Outbound time + return time = 5 hrs
d%2F270 + d%2F330 = 5
:
Multiply equation by a multiple of 270 and 330, 89100 will do it:
330d + 270d = 5(89100)
:
600d = 445500
d = 445500%2F600
d = 742.5 miles max distance
:
However, they use the word "safely", I doubt they would exceed 700 mi from home