Question 451668: "Traveling for 4 hours into a steady head wind, a plane flies 1200 miles. The plane can make the return trip, flying with the wind, in 3 hours. Find the speed of the plane and the speed of the wind.
Show :
1) Define two variables
2) Write a system of equations
3) Solve the system of equations
4) Answer the question"
Please help! :O
Answer by lwsshak3(11628)   (Show Source):
You can put this solution on YOUR website! "Traveling for 4 hours into a steady head wind, a plane flies 1200 miles. The plane can make the return trip, flying with the wind, in 3 hours. Find the speed of the plane and the speed of the wind.
Show :
1) Define two variables
2) Write a system of equations
3) Solve the system of equations
4) Answer the question"
..
1)
let x=speed of plane
let w=speed of wind
(x+w)=Speed of plane with wind
(x-w)=Speed of plane against wind
2)
Travel time=distance/speed
1200/(x+w)=3
1200/(x-w)=4
3)
3x+3w=1200
4x-4w=1200
..
3)
12x+12w=4800 (multiply by 4)
12x-12w=3600 (multiply by 3)
24x=8400
x=350
12w=4800-12*350
12w=60
w=5
..
4)
answers:
speed of plane=350 mph
windspeed=5 mph
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