SOLUTION: Flying against the jetstream, a jet travels 5250km in 7 hours. Flying with the jetstream, the same jet travels 4920km in 4 hours. What is the speed of the jet in still air, and wh
Algebra ->
Customizable Word Problem Solvers
-> Travel
-> SOLUTION: Flying against the jetstream, a jet travels 5250km in 7 hours. Flying with the jetstream, the same jet travels 4920km in 4 hours. What is the speed of the jet in still air, and wh
Log On
Question 144430: Flying against the jetstream, a jet travels 5250km in 7 hours. Flying with the jetstream, the same jet travels 4920km in 4 hours. What is the speed of the jet in still air, and what is the speed of the jetstream?
You can put this solution on YOUR website! Flying against the jetstream, a jet travels 5250km in 7 hours. Flying with the jetstream, the same jet travels 4920km in 4 hours. What is the speed of the jet in still air, and what is the speed of the jetstream?
:
Let s = jet's speed in still air:
Let w = jet-stream's speed
:
Two dist equations
7(s-w) = 5250
4(s+w) = 4920
:
Simplify both equation: divide the 1st eq by 7, divide the 2nd eq by 4, results:
s - w = 750
s + w = 1230
--------------adding eliminates w, find s
2s +0 = 1980
s =
s = 990 km/hr speed in still air
:
Find w
s + w = 1230
990 +w =1230
w = 1230 - 990
w = 240 km/hr
:
Check solutions:
7(990-240) = 5250
