Answer
$\dfrac{138}{5} \text{ } cm$
Work Step by Step
$\bf{\text{Solution Outline:}}$
Change the given length of the cube, $
2\frac{3}{10}
,$ to an improper fraction. Then multiply the result by $12$ to get the total length of the edges of the cube.
$\bf{\text{Solution Details:}}$
The mixed number, $a\frac{b}{c},$ is equivalent to $\dfrac{ac+b}{c}.$ Hence, the given length of the edge of the cube is equivalent to
\begin{array}{l}\require{cancel}
2\frac{3}{10}
\\\\=
\dfrac{2(10)+3}{10}
\\\\=
\dfrac{23}{10}
.\end{array}
Since a cube has a total of $12$ equal edges, then the total length of the edges of the cube is
\begin{array}{l}\require{cancel}
\dfrac{23}{10}\cdot12
\\\\=
\dfrac{23}{\cancel2(5)}\cdot\cancel2(6)
\\\\=
\dfrac{138}{5} \text{ } cm
.\end{array}
