SOLUTION: Against the wind, a plane flew 715 miles in 2 hours and 10 min. the return trip took only 1 hour and 30 minutes. what was the speed of the wind and what was the speed of the plane

Algebra ->  Customizable Word Problem Solvers  -> Travel -> SOLUTION: Against the wind, a plane flew 715 miles in 2 hours and 10 min. the return trip took only 1 hour and 30 minutes. what was the speed of the wind and what was the speed of the plane       Log On

Ad: Over 600 Algebra Word Problems at edhelper.com


    

Question 941691: Against the wind, a plane flew 715 miles in 2 hours and 10 min. the return trip took only 1 hour and 30 minutes. what was the speed of the wind and what was the speed of the plane in still air
Answer by lwsshak3(11628) About Me  (Show Source):
You can put this solution on YOUR website!
Against the wind, a plane flew 715 miles in 2 hours and 10 min. the return trip took only 1 hour and 30 minutes. what was the speed of the wind and what was the speed of the plane in still air.
***
let x=speed of plane in still air
let c=speed of wind
x+c=speed of plane with the wind
x-c=speed of plane against the wind
travel time*speed=distance
..
2 hr 10 min=2 1/6 hr=13/6 hr
1 hr 30 min= 3/2 hr
..
13/6*(x-c)=715
3/2*(x+c)=715
..
13(x-c)=6*715
3(x+c)=2*715
..
13x-13c=4290
3x+3c=1430
..
39x-39c=12870 (mult. eq by 3)
39x+39c=18590 (mult. eq by 13)
add
78x=31460
x=403 1/3
..
subtract:
-78c=-5720
c=73 1/3
speed of plane in still air=403 1/3 mph
speed of wind=73 1/3 mph