Answer:
The speed of the wind is [tex]35\ mph[/tex]
Step-by-step explanation:
Let
x-----> the speed of the wind in mph
we know that
Downwind
[tex](255+x)=\frac{290}{t}[/tex]
[tex]t=\frac{290}{(255+x)}[/tex] -----> equation A
Upwind
[tex](255-x)=\frac{220}{t}[/tex]
[tex]t=\frac{220}{(255-x)}[/tex] ----> equation B
equate the equation A and the equation B
[tex]\frac{290}{(255+x)}=\frac{220}{(255-x)}\\ \\290(255-x)=220(255+x)\\ \\ 73,950-290x= 56,100x+220x\\ \\220x+290x=73,950-56,100\\ \\510x=17,850\\ \\x= 35\ mph[/tex]