GitHub etiquette: Should I submit a pull request to correct minor typos in a Readme file?

While going through the README file of a GitHub repository I am not a contributor of, I noticed a few minor typos and wondered if I should submit a pull request to correct them or if reviewing the request would take the maintainer too much time to be worth it. I considered the three courses of action:

  1. Correct the typos and submit a pull request with the position of each correction in the summary field.
  2. Send the maintainer an email with the proposed corrections.
  3. Do nothing.

Which of these (or any other) options is most appropriate?

To give some context, the repository is actively maintained and has about 10 contributors. The typos I have noticed do not make the README misleading nor ambiguous. I have used GitHub for some time for small personal projects, but have little experience with pull requests and how much time and efforts they take to review (hence my question).