Answer
False.
In this case, $y$ is directly proportional to $z$
Work Step by Step
$a,b,c$ are constants.
$y=a\frac{1}{x}$
$x=b\frac{1}{z}$. Replace this equation in the above equation.
$y=a\frac{1}{b\frac{1}{z}}=\frac{a}{b}(1)\frac{z}{1}=\frac{a}{b}z$
$y=cz$, where $c=\frac{a}{b}$
