Answer
S is larger than $S_{100}$.
Work Step by Step
In this case, $S$ is an alternating series and hence $$|S-S_{100}|\lt a_{101}=10^{-3}.$$
You can help us out by revising, improving and updating this answer.
Update this answerAfter you claim an answer you’ll have 24 hours to send in a draft. An editor will review the submission and either publish your submission or provide feedback.