Answer
The speed of the wind $3v$ is 30 mph. The wind $3v$ is 3 times faster than $v$ and it is blowing in the same direction as $v$.
Work Step by Step
$v = 6~i+8~j$
$3v = 18~i+24~j$
The speed of the wind is the magnitude of the vector $3v$. We can find the magnitude of the vector $3v$:
$\vert 3v \vert = \sqrt{18^2+24^2}$
$\vert 3v \vert = 30$
The speed of the wind $3v$ is 30 mph. The wind $3v$ is 3 times faster than $v$ and it is blowing in the same direction as $v$.
