Problem:
Compute the following expression: $\sum_{k=0}^3 -\frac{15}{62}\frac{1}{\sqrt{7}}^k$
Answer:
$-\frac{60}{217}-\frac{60}{217 \sqrt{7}}$
{'source': 'AMPS', 'file': 'amps/mathematica/algebra/geometric_series/48791.txt'}