SOLUTION: A plane can travel 350 km/h in still air. With the wind it flew 1000 km. In the same amount of time it could travel 750 km against the wind. Find the speed of the wind.

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Question 555059: A plane can travel 350 km/h in still air. With the wind it flew 1000 km. In the same amount of time it could travel 750 km against the wind. Find the speed of the wind.
Answer by ankor@dixie-net.com(22740) About Me  (Show Source):
You can put this solution on YOUR website!
A plane can travel 350 km/h in still air. With the wind it flew 1000 km.
In the same amount of time it could travel 750 km against the wind.
Find the speed of the wind.
:
Let w = speed of the wind
then
(350-w) = effective speed against the wind
and
(350+w) = effective speeed with
:
Write a time equation: time = dist/speed
:
1000%2F%28%28350%2Bw%29%29 = 750%2F%28%28350-w%29%29
Cross multiply
1000(350-w) = 750(350+w)
simplify divide both sides by 250, results
4(350-w) = 3(350+w)
1400 - 4w = 1050 + 3w
1400 - 1050 = 7w + 4w
350 = 7w
w = 350%2F7
w = 50 mph is the speed of the wind
:
:
Confirms this find the times of each trip
1000/400 = 2.5 hrs
750/300 = 2.5