Question 894281: A plane traveled 1248 miles to Kampala and back. The trip there was with wind. It took 13 hours. The trip back was into the wind. The trip back took 26 hours. What is the speed of the plane in still air? What is the speed of wind?
Answer by ankor@dixie-net.com(22740)   (Show Source):
You can put this solution on YOUR website! A plane traveled 1248 miles to Kampala and back.
The trip there was with wind. It took 13 hours.
The trip back was into the wind. The trip back took 26 hours.
What is the speed of the plane in still air?
What is the speed of wind?
:
Let s = plane speed in still air
let w = speed of the wind
then
(s+w) = ground speed with the wind
and
(s-w) = ground speed against the wind
:
Write a dist equation for each way (dist = speed * time)
13(s+w) = 1248
26(s-w) = 1248
Simplify divide the 1st equation by 13, and the 2nd equation by 26, you have:
s + w = 96
s - w = 48
------------Adding eliminates w, find s
2s = 144
s = 144/2
s = 72 mph plane speed in still air
Find the wind speed
72 + w = 96
w = 24 mph is the wind speed
:
:
You can confirm this for yourself, check this in both original equations
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