Answer
$BA=\left[ {\begin{array}{*{20}{c}}
{\$ 1037.5}&{\$ 1400}&{\$ 1012.5}
\end{array}} \right]$
Each entry of the matrix represents the total profit from the corresponding outlets.
Work Step by Step
We have:
$B= \left[ {\begin{array}{*{20}{c}}
\$3.5&\$6\\
\end{array}} \right]$
and
$A= \left[ {\begin{array}{*{20}{c}}
125&100&75\\
100&175&125
\end{array}} \right]$
Then
$\begin{array}{l}
BA = \left[ {\begin{array}{*{20}{c}}
{\$ 3.5}&{\$ 6}
\end{array}} \right].\left[ {\begin{array}{*{20}{c}}
{125}&{100}&{75}\\
{100}&{175}&{125}
\end{array}} \right]\\
= \left[ {\begin{array}{*{20}{c}}
{\$ (3.5 \times 125 + 6 \times 100)}&{\$ (3.5 \times 100 + 6 \times 175)}&{\$ (3.5 \times 75 + 6 \times 125)}
\end{array}} \right]\\
= \left[ {\begin{array}{*{20}{c}}
{\$ 1037.5}&{\$ 1400}&{\$ 1012.5}
\end{array}} \right]
\end{array}$
Each entry of the matrix represents the total profit from the corresponding outlets.
