#### Answer

$x\approx0.368$

#### Work Step by Step

In exponential form, the given logarithmic equation, $
3\ln x=-3
,$ is equivalent to
\begin{array}{l}\require{cancel}
\ln x=-\dfrac{3}{3}
\\\\
\ln x=-1
\\\\
\log_e x=-1
\\\\
x=e^{-1}
.\end{array}
Hence, the value of the variable that satisfies the given equation is
\begin{array}{l}\require{cancel}
x\approx0.368
.\end{array}