Problem:
Compute the mean of ${\frac{11}{\pi }, -\frac{19}{\pi }, \frac{12}{\pi }, -\frac{6}{\pi }, -\frac{15}{\pi }, -\frac{26}{\pi }, \frac{7}{\pi }}$.
Answer:
$-\frac{36}{7 \pi }$
{'source': 'AMPS', 'file': 'amps/mathematica/counting_and_statistics/mean/16160.txt'}