Question 176747: Flying against the jetstream, a jet travels 4410km in 9 hours. Flying with the jetstream, the same jet travels 7280 km in 8 hours. What is the speed of the jet in still air, and what is the speed of the jetstream?
I saw this question but it was a little different can you help please thanks.
Answer by ankor@dixie-net.com(22740)   (Show Source):
You can put this solution on YOUR website! Flying against the jetstream, a jet travels 4410km in 9 hours. Flying with the jetstream, the same jet travels 7280 km in 8 hours. What is the speed of the jet in still air, and what is the speed of the jetstream?
:
let x = speed of the jet
let y = jet-stream speed
;
Write a distance equation dist = time*speed
9(x-y) = 4410
8(x+y) = 7280
;
simplify: divide the 1st eq by 8 and th 2nd eq by 9:
x - y = 490
x + y = 910
---------------adding eliminates y, find x
2x = 1400
x = 1400/2
x = 700 km/hr jet speed
;
;
find y using x - y = 910
700 + y = 910
y = 910 - 700
y = 210 km/hr jet-stream speed
;
you can check solutions in original eq's
|
|
|
