SOLUTION: PLEASE HELP ASAP:Flying against the jetstream, a jet travels 4240km in 8 hours. Flying with the jetstream, the plane travels 2910km in 3 hours. What is the speed of the jet in st

Algebra ->  Coordinate Systems and Linear Equations  -> Linear Equations and Systems Word Problems -> SOLUTION: PLEASE HELP ASAP:Flying against the jetstream, a jet travels 4240km in 8 hours. Flying with the jetstream, the plane travels 2910km in 3 hours. What is the speed of the jet in st      Log On


   

Question 28492: PLEASE HELP ASAP:Flying against the jetstream, a jet travels 4240km in 8 hours. Flying with the jetstream, the plane travels 2910km in 3 hours. What is the speed of the jet in still air, and what is the speed of the jetstream?
Thank you so much
Answer by Paul(988) About Me  (Show Source):
You can put this solution on YOUR website!
Let the speed of the wind be y
Let the speed of the plane be y


8x-8y=4240
second equation:
3(x+y)=2910
3x+3y=2910

Multiply the first equation by 3 and the second equatin by 8
24x-24y=12720
24x+24y=23280
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48x=36000
x=750

3(750)+3y=2910
3y=660
y=220

Hence, the speed of the jetstream is 220mph and the speed of the plane is 750mph.
Paul.