Answer
See below.
Work Step by Step
We can see that the sequence of numbers starts with $-\frac{2}{5}$, the signs are alternating and the numerator and denominator increase by $1$ in each term until they reach $11$ and $14$ respectively. Thus a summation formula is: $\sum_{i=1}^{10}(-1)^i \frac{i+1}{i+4}$
