SOLUTION: If a plane can travel 490 miles per hour with the wind and 410 miles per hour against the wind, find the speed of the plane in still air. What is the speed of the plane in still a

Algebra ->  Coordinate Systems and Linear Equations -> SOLUTION: If a plane can travel 490 miles per hour with the wind and 410 miles per hour against the wind, find the speed of the plane in still air. What is the speed of the plane in still a      Log On


   

Question 1013391: If a plane can travel 490 miles per hour with the wind and 410 miles per hour against the wind, find the speed of the plane in still air.
What is the speed of the plane in still air?
___ miles per hour
Found 2 solutions by josgarithmetic, macston:
Answer by josgarithmetic(39617) About Me  (Show Source):
You can put this solution on YOUR website!
r, the rate of the plane without being in wind;
w, the speed of the wind;
system%28r%2Bw=490%2Cr-w=410%29

Very simple two-variable linear system, perfectly ready for solving with Elimination Method. If you ADD the corresponding members, this will eliminate w, and you can quickly find the value for r.

Answer by macston(5194) About Me  (Show Source):
You can put this solution on YOUR website!
.
S=speed in still air; W=wind speed
.
S-W=410 mph
S=W+410 mph
,
S+W=490
(W+410mph)+W=490 mph
2W+410mph=490mph
2W=80mph
W=40mph
Wind speed is 40 mph.
.
S=W+410mph=40mph+410mph=450 mph
ANSWER: Speed in still air is 450 mph.