Answer:
-88 mph
Step-by-step explanation:
We can use the relation ...
time = distance/speed
to compare the times in the two directions.
[tex]\dfrac{140}{200+w}=\dfrac{360}{200-w}\\\\140(200-w)=360(200+w)\\\\200(140-360)=w(360+140)\\\\w=\dfrac{200(-220)}{500}=-88 \quad\text{miles per hour}[/tex]
The wind speed is -88 miles per hour.
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The problem statement tells us the travel is slower with the wind than against the wind. Hence "with the wind" must be subtracting from the net speed. That is, the wind speed is negative.
