Question 1124623
.
An airplane can fly 550 miles with the wind in the same amount of time it takes to fly 425 miles against the wind. 
Find the speed of the wind, if the airplane is flying at a constant speed of 195 miles per hour {{{highlight(at_no_wind)}}}.
~~~~~~~~~~~~~~~~~~


<pre>
Let r be the speed of the wind.


The time equation is


{{{550/(195+r)}}} = {{{425/(195-r)}}}


To solve it, cross multiply


550*(195-r) = 425*(195+r)


Divide both sides by 25


22*(195-r) = 17*(195+r)


22*195 - 22r = 17*195 + 17r


22*195 - 17*195 = 22r + 17r


r = {{{(22*195 - 17*195)/(22+17)}}} = 25 miles per hour.


<U>Answer</U>.  The speed of the wind is 25 miles per hour.
</pre>

Solved.