SOLUTION: A plane traveled 644 miles to Austin and back. The trip there was with the wind. It took 7 hours. the trip back was into the wind. The trip took 14 hours. What is the speed of the
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Question 895698: A plane traveled 644 miles to Austin and back. The trip there was with the wind. It took 7 hours. the trip back was into the wind. The trip took 14 hours. What is the speed of the plane in still air? What is the speed of the wind?
You can put this solution on YOUR website! A plane traveled 644 miles to Austin and back. The trip there was with the wind. It took 7 hours. the trip back was into the wind. The trip took 14 hours. What is the speed of the plane in still air? What is the speed of the wind?
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Use d = r*t --> r = d/t to find the 2 groundspeeds.
The plane's airspeed is the average of them.
The windspeed is the difference between airspeed and groundspeed.
You can put this solution on YOUR website! A plane traveled 644 miles to Austin and back. The trip there was with the wind. It took 7 hours. the trip back was into the wind. The trip took 14 hours. What is the speed of the plane in still air? What is the speed of the wind?
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let x=speed of plane in still air
let c=speed of wind
x+c=speed of plane with wind
x-c=speed of plane into wind
Distance/speed=travel time
..
644/(x+c)=7
644/(x-c)=14
..
7x+7c=644
14x-14c=644
..
14x+14c=1288 (mult. by 2)
14x-14c=644
add
28x=1932
x=69
7c=644-7x
7c=161
c=23
speed of plane in still air=69 mph
speed of wind=23 mph