Question 1152505
If w is speed of wind then helicopter speed is capable of 5w.

<pre>
                 SPEED      TIME              DISTANCE          

UPWIND           5w-w       800/(5w-w)           800

DOWNWIND         5w+w       600/(5w+w)           600

DIFF                           2
</pre>
{{{highlight_green(800/(4w)-600/(6w)=2)}}}, and question asks for {{{5w}}}.


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READ THE PROBLEM AGAIN.  LOOK AT THE TABLE OF INFORMATION FORMED.  DO YOU UNDERSTAND THE EQUATION?  SOLVE FOR w.  THE QUESTION ASKS FOR 5w.