Question 316822
Rate*Time=Distance
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Let P be the plane speed in still air, W be the wind speed.
With the wind,
{{{(P+W)*2.5=785}}}
1.{{{P+W=314}}}
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Against the wind,
{{{(P-W)*3=785}}}
2.{{{P-W=785/3}}}
Add eq.1 to eq. 2,
{{{P+W+P-W=314+785/3}}}
{{{2P=942/3+785/3}}}
{{{2P=1727/3}}}
{{{P=1727/6}}}
Then use either equation to solve for W.
{{{1727/6+W=314}}}
{{{W=1884/6-1727/6}}}
{{{W=157/6}}} or approximately,
{{{highlight(W=26)}}} mph