Answer
$y=\displaystyle \frac{3}{4x}$
Work Step by Step
If y varies inversely with x, then $y=\displaystyle \frac{k}{x}$, for some constant k.
Given x=$\displaystyle \frac{1}{4}$, y=$3$, we find k
$3=\displaystyle \frac{k}{\frac{1}{4}}$
$ 3=4k\qquad$ ... divide with 4
$\displaystyle \frac{3}{4}=k$
So,
$y=\displaystyle \frac{3}{4x}$
