Here we can say that net speed against the wind is given by
[tex]V_{plane} - v_{wind} = \frac{distance}{time}[/tex]
[tex]V_{plane} - v_{wind} = \frac{3624}{6}[/tex]
[tex]V_{plane} - v_{wind} = 604 mph[/tex]
also if it is moving along the direction of wind we will have
[tex]V_{plane} + v_{wind} = \frac{distance}{time}[/tex]
[tex]V_{plane} + v_{wind} = \frac{4764}{6}[/tex]
[tex]V_{plane} + v_{wind} = 794 mph[/tex]
now add the above two equations we will have
[tex]V_{plane} = 699 mph[/tex]
also we can say
[tex]v_{wind} = 95 mph[/tex]