Problem:
Multiply
$\left(
\begin{array}{c}
 -\frac{5}{7} \\
\end{array}
\right)$ and
$\left(
\begin{array}{cccc}
 -\frac{8}{7} & \frac{10}{7} & \frac{4}{7} & -3 \\
\end{array}
\right)$.
Answer:
$\left(
\begin{array}{cccc}
 \frac{40}{49} & -\frac{50}{49} & -\frac{20}{49} & \frac{15}{7} \\
\end{array}
\right)$
{'source': 'AMPS', 'file': 'amps/mathematica/linear_algebra/multiply/11624.txt'}