#### Answer

$-3$

#### Work Step by Step

$\bf{\text{Solution Outline:}}$
Interchange the numerator and the denominator to get the reciprocal of the given expression, $
-\dfrac{1}{3}
.$
$\bf{\text{Solution Details:}}$
Interchanging the numerator and the denominator, the reciprocal of the given expression is
\begin{array}{l}\require{cancel}
-\dfrac{3}{1}
\\\\=
-3
.\end{array}