An airplane took 3 hours to fly 1200 miles against a headwind. The return trip with the wind took 2 hours. Find the speed of the plane in still air and the speed of the wind.

Question

anonymous · Answer

let rate of plane in still air be x
let rate of wind be y 
(x-y)*4 =1200 
(x+y)*3=1200 

4x-4y=1200 
3x+3y=1200 
3(4x-4y)+4(3x+3y)=3*1200+4*1200 
12x-12y + 12x +12y = 8400 
24x=8400
x=350 mph rate of plane in still air 

 
(x+y)*3=1200
(350+y)*3 =1200 
1050+3y=1200 
3y=1200-1050 
3y= 150 
y=50 mph rate of wind