Question 620512: An aircraft slew 5 hours with the wind. The return trip took 6 hours against the wind. If the speed of the plane in still air is 190 miles per hour more than the speed of the wind, find the wind speed 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! An aircraft slew 5 hours with the wind.
The return trip took 6 hours against the wind.
If the speed of the plane in still air is 190 miles per hour more than the speed of the wind, find the wind speed and the speed of the plane in still air.
:
Let s = speed that the plane "slew"
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; dist = time * speed.
:
There dist = Return dist
5(s+w) = 6(s-w)
5s + 5w = 6s - 6w
5w + 6w = 6s - 5s
11w = s
:
It says,"the speed of the plane in still air is 190 miles per hour more than the speed of the wind, "
therefore
s = (w+190)
Replace s with 11w
11w = w + 190
11w - w = 190
10w = 190
w = 19 mph is the rate of the wind
then
s = 19 + 190
s = 209 is the speed of the plane in still air
:
You can check this in the first equation
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