Problem:
Add the two matrices
$\left(
\begin{array}{ccc}
 -\frac{15}{2} & \frac{21}{4} & \frac{19}{2} \\
 \frac{29}{4} & -\frac{5}{2} & \frac{31}{4} \\
 -\frac{17}{4} & \frac{7}{4} & -\frac{5}{2} \\
 -\frac{5}{4} & \frac{1}{4} & -\frac{9}{4} \\
\end{array}
\right)$ and
$\left(
\begin{array}{ccc}
 \frac{23}{4} & \frac{7}{2} & -\frac{35}{4} \\
 \frac{37}{4} & 4 & -3 \\
 -\frac{31}{4} & \frac{11}{4} & -\frac{3}{4} \\
 -8 & -3 & \frac{3}{2} \\
\end{array}
\right)$
Answer:
$\left(
\begin{array}{ccc}
 -\frac{7}{4} & \frac{35}{4} & \frac{3}{4} \\
 \frac{33}{2} & \frac{3}{2} & \frac{19}{4} \\
 -12 & \frac{9}{2} & -\frac{13}{4} \\
 -\frac{37}{4} & -\frac{11}{4} & -\frac{3}{4} \\
\end{array}
\right)$
{'source': 'AMPS', 'file': 'amps/mathematica/linear_algebra/add/12275.txt'}