SOLUTION: a plane takes 3 hours to travel 1,503 miles with the wind. It can travel only 1,179 miles against the wind in the same time. Find the speed of the wind and the speed of the plane i

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Question 267731: a plane takes 3 hours to travel 1,503 miles with the wind. It can travel only 1,179 miles against the wind in the same time. Find the speed of the wind and the speed of the plane in still air.
Answer by ankor@dixie-net.com(22740) (Show Source):
You can put this solution on YOUR website!
a plane takes 3 hours to travel 1,503 miles with the wind.
It can travel only 1,179 miles against the wind in the same time.
Find the speed of the wind and the speed of the plane in still air.
:
Let s = still air speed of the plane
Let w = speed of the wind
then
(s-w) = effective speed against the wind
and
(s+w) = effective speed with the wind
;
Write a distance equation for each trip; Dist = time * speed
:
3(s + w) = 1503
3(s - w) = 1179
we can simplify both of these, divide by 3
s + w = 501
s - w = 393
-------------addition eliminates w
2s = 894
s =
s = 447 mph in still air
:
Find w
447 + w = 501
w = 501 - 447
w = 54 mph is the wind
:
:
Check solution in the 2nd equation
3(447 - 54) =
3(393) = 1179 mi